Observations in A Sentence

    1

    A few observations of a general character will therefore suffice in this place.

    2

    A formula of this type has been widely employed by van't Hoff and others to calculate heats of reaction and solution from observations of solubility and vice versa.

    3

    A Log Book is a marine or sea journal, containing, in the British navy, the speed, course, leeway, direction and force of the wind, state of the weather, and barometric and thermometric observations.

    4

    A physicist, however, does more than merely quantitatively determine specific properties of matter; he endeavours to establish mathematical laws which co-ordinate his observations, and in many cases the equations expressing such laws contain functions or terms which pertain solely to the chemical composition of matter.

    5

    A series of observations can be easily and more accurately accomplished with the Cape heliometer in half an hour; with the Oxford heliometer it would occupy 2 hours, and with the 4-in.

    6

    According to Joule's observations, the length of a bar of iron or soft steel was increased by magnetization, the elongation being proportional up to a certain point to the square of the intensity of magnetization; but when the " saturation point " was approached the elongation was less than this law would require, and a stage was finally reached at which further increase of the magnetizing force produced little or no effect upon the length.

    7

    According to numerous observations made at Cape Thorsden, the apparent angular velocity of arcs increases on the average with their altitude.

    8

    According to observations extending from 1706 to 1899, the mean day of the freezing of the Neva is November 25th, the earliest October 28th, the latest January 9th, and the next latest December 26th.

    9

    According to the law of Avogadro, equal volumes of different gases under the same conditions of temperature and pressure contain equal numbers of molecules; therefore, since the density depends upon the number of molecules present in unit volume, it follows that for a comparison of the densities of gases, the determinations must be made under coincident conditions, or the observations reduced or re-computed for coincident conditions.

    10

    After his death (which occurred soon after that of his friend) these were purchased by Dr Worthington, of Cambridge; and from his hands the treatise Venus in sole visa passed into those of Hevelius, and was published by him in 1662 with his own observations on a transit of Mercury.

    11

    After remaining two days at the Pole to secure sufficient observations to fix the position, Amundsen and his party returned to Framheim in 38 days, picking up the depots in succession and making an average of 23 m.

    12

    After Wood and Moore had confirmed and extended the observations of Wiedemann and Schmidt and.

    13

    All patent logs have errors, the amounts of which should be ascertained by shore observations when passing a well surveyed coast in tideless waters on a calm day.

    14

    Also, whilst the mean azimuths deduced from the observations between 6 A.M.

    15

    Alston's observations were founded on what occurred in certain unisexual plants, such as Mercurialis, Spinach, Hemp, Hop and Bryony.

    16

    Although observations on marine currents were made near land or between islands even in antiquity, accurate observations on the high seas have only been possible since chronometers furnished a practicable method of determining longitude, i.e.

    17

    America, he made observations on the geology, published by the Geological Society in 1860.

    18

    Among the contributors of Freron was another manufacturer of criticism, the abbe de la Porte, who, having quarrelled with his confrere, founded Observations sur la litterature moderne (1749-1752) and L'Observateur litteraire (1758-1761).

    19

    Among the most ardent of his followers was Francois Joseph Victor Broussais (1772-1838), whose theoretical views, partly founded on those of Brown and partly on the so-called vitalist school of Theophile Bordeu (1722-1776) and Paul Joseph Barthez (1734-1806), differed from these essentially in being avowedly based on anatomical observations.

    20

    An additional difficulty arises in the case of observations made with long mercury thermometers buried in vertical holes, that the correction for the expansion of the liquid in the long stems is uncertain, and that the holes may serve as channels for percolation, and thus lead to exceptionally high values.

    21

    An appeal made by Miller for observations on the development of the Caeciliae, and of those Amphibia which retain gills or gill-clefts throughout life, has unfortunately yielded no fruits.

    22

    An early observatory, where in 1822 were made the observations for the Parramatta Catalogue, numbering 7385 stars, has long been abandoned.

    23

    An idea of the disturbing influence of cloud may be derived from some interesting results from the Cape Thorsden (7) observations.

    24

    An immense mass of material has been collected on the subject of vapour-pressures and densities, the greater part of which will be found in Winkelmann's Handbook, in Landolt's and Bornstein's Tables, and in similar compendiums. The results vary greatly in accuracy, and are frequently vitiated by errors of temperature measurement, by chemical impurities and surface condensation, or by peculiarities of the empirical formulae employed in smoothing the observations; but it would not be within the scope of the present article to discuss these details.

    25

    An increasing number of workers in this field of plant biology in England, on the Continent and in America has produced a great mass of observations, which have recently been brought together in Dr Paul Knuth's classic work, Handbook of Flower Pollination, an English translation of which has been published (1908) by the Clarendon Press.

    26

    An inquirer who examines the stars with a shilling telescope is not likely to make observations of value, and even a trained astronomer has to allow for his "personal equation" - a point to which even a finished critic rarely attends.

    27

    An interesting letter from him, dated the 10th of April, 1716, is printed in the Lettres edifiantes, rec. xv., and he left a large MS. volume of his observations.

    28

    Annual Variation.-When observations are made at irregular hours, or at only one or two fixed hours, it is doubtful how representative they are.

    29

    Aperture, and a Selection from the Observations of Nebulae made with them," with numerous engravings.

    30

    As clerk (1795) and then as supercargo (1796, 1798, 1799) he made four long voyages; and, being an excellent navigator, he afterwards (1802) commanded a vessel, instructing his crews in lunar and other observations.

    31

    As early as 1831 (during the annular eclipse of the sun) she had been her father's assistant in his observations.

    32

    As regards the struthious birds, they could not be likened to the duck, for in them at no age was there any indication of a single median centre of ossification, as Geoffroy had satisfied himself by his own observations made in Egypt many years before.

    33

    As the Arctic Basin is shut off from the North Atlantic by ridges rising to within 300 fathoms of the surface and from the Pacific by the shallow shelf of the Bering Sea, and as the ice-laden East Greenland and Labrador currents consist of fresh surface water which cannot appreciably influence the underlying mass, the Arctic region has no practical effect upon the bottom temperature of the three great oceans, which is entirely dominated by the influence of the Antarctic. The existence of deep-lying and extensive rises or ridges in high southern latitudes has been indicated by the deep-sea temperature observations of Antarctic expeditions.

    34

    As to colour, he follows Goethe, and uses strong language against Newton's theory, for the barbarism of the conception that light is a compound, the incorrectness of his observations, &c. In chemistry, again, he objects to the way in which all the chemical elements are treated as on the same level.

    35

    As to the details, the following observations 2 may be made for the last phase of the empire which expired in 1918.

    36

    Assured that his explanation was true, Bradley corrected his observations for aberration, but he found that there still remained a residuum which was evidently not a parallax, for it did not exhibit an annual cycle.

    37

    Astronomical observations extend over too brief a period of time to show any attraction between different stars except those in each other's neighbourhood.

    38

    At first an apothecary, he turned his attention to astronomy, and in 1826 commenced his observations on sun-spots.

    39

    At the most important stations observations are taken everyhour; at the less important, six observations daily; and at the least important, three observations.

    40

    At the same time temperature observations are made.

    41

    At this height, with the thermometer marking 9 degrees below freezing, he remained for a considerable time, making observations not only on magnetism, but also on the temperature and humidity of the air, and collecting several samples of air at different heights.

    42

    Balard discovered chlorine monoxide in 1834, investigating its properties and reactions; and his observations on hypochlorous acid and hypochlorites led him to conclude that " bleaching-powder " or " chloride of lime " was a compound or mixture in equimolecular proportions of calcium chloride and hypochlorite, with a little calcium hydrate.

    43

    Bamberger's observations on reduced quinoline derivatives point to the same conclusion, that condensed nuclei are not benzenoid, but possess an individual character, which breaks down, however, when the molecule is reduced.

    44

    Becoming interested in terrestrial magnetism he made many observations of magnetic intensity and declination in various parts of Sweden, and was charged by the Stockholm Academy of Sciences with the task, not completed till shortly before his death, of working out the magnetic data obtained by the Swedish frigate "Eugenie" on her voyage round the world in 1851-1853.

    45

    Benjamin Franklin in 1775 and Charles Blagden in 1781, by means of numerous observations of temperature made on board the packets plying on the Atlantic passage, determined the boundaries of these two currents and their seasonal variations with considerable precision.

    46

    Besides being one of the sights of Paris, to which visitors resort in order to enjoy the extensive view that can be had from its higher galleries on a clear day, the tower is used to some extent for scientific and semi-scientific purposes; thus meteorological observations are carried on.

    47

    Besides giving to the world the first accurate description of the holy city and the Haj ceremonies, he was the first to fix the position of Mecca by astronomical observations, and to describe the physical character of its surroundings.

    48

    Besides his great work, Malthus wrote Observations on the Effect of the Corn Laws; An Inquiry into the Nature and Progress of Rent; Principles of Political Economy; and Definitions in Political Economy.

    49

    Bjerknes have been usefully applied in many cases, but they cannot take the place of direct observations of currents and of the fundamental processes and conditions underlying them.

    50

    Blakeslee has lately made some very important observations of the Zygomycetes.

    51

    Blanchard published some Recherches sur les caracteres osteo- logiques des oiseaux appliquees a la classification naturelle de ces animaux, strongly urging the superiority of such characters over those drawn from the bill or feet, which, he remarks, though they may have sometimes given correct notions, have mostly led to mistakes, and, if observations of habits and food have sometimes afforded happy results, they have often been deceptive; so that, should more be wanted than to draw up a mere inventory of creation or trace the distinctive outline of each species, zoology without anatomy would remain a barren study.

    52

    Bossert's catalogue (Paris Observations, 1890), which consist of lists of stars of large proper motion determined from a variety of sources.

    53

    Bradley had already perceived, in the case of the two stars previously scrutinized, that the apparent difference of declination from the maximum positions was nearly proportional to the sun's distance from the equinoctial points; and he realized the necessity for more observations before any generalization could be attempted.

    54

    But in the following observations we deal generally with the more important features of riding as practised astride.

    55

    But it is more probable that we have it in the form in which it grew up - a series of observations by the original author with interspersed editorial remarks; and it is better to preserve the existing form as giving a record of the process of growth.

    56

    But the combination of observations and theory on which this is based is not sufficient fully to establish so slight a motion.

    57

    But the Peckhams' careful observations and experiments show that, with the American wasps, the victims stored in the nests are quite as often dead as alive; that those which are only paralysed live for a varying number of days, some more, some less; that wasp larvae thrive just as well on dead victims, sometimes dried up, sometimes undergoing decomposition, as on living and paralysed prey; that the nerve-centres are not stung with the supposed uniformity; and that in some cases paralysis, in others death, follows when the victims are stung in parts far removed from any nerve-centre.

    58

    But they did justice to the acuteness of his observations on morals and manners, to the constant precision and frequent brilliancy of his language, to the weighty and magnificent eloquence of many serious passages, and to the solemn yet pleasing humour of some of the lighter papers.

    59

    But when the wind is steady its effect may be eliminated by " reciprocal " observations, that is, by observations of the time of passage of sound in each direction over the measured distance..

    60

    But when we come to study his observations on the natural history of disease as presented in the living subject, we recognize at once the presence of a great clinical physician.

    61

    But while Forbes asserted that ice was viscous, Tyndall denied it, and insisted, as the result of his observations, on the flow being due to fracture and regelation.

    62

    But, at the same time, the constants in the above relation are not identical with those in the corresponding relation empirically deduced from observations on fatty hydrocarbons; and we are therefore led to conclude that a benzene union is considerably more stable than an ethylene union.

    63

    By 1904 more than 6800 of these meteorological logs with 7,000,000 observations had been accumulated by the Meteorological Office in London; 20,000 with io,600,000 observations by the German Marine Observatory at Hamburg; 4700 with 3,300,000 observations by the Central Institute of the Netherlands at de Bilt near Utrecht.

    64

    By a skilful division of labour, and by the erection of numerous observing stations, the mapping out of the whole coast proceeded simultaneously under the eye of the general director, and in addition a vast mass of magnetic and meteorological observations was collected.

    65

    By actual observations it has been shown that ether, alcohol, many esters of the normal alcohols and fatty acids, benzene, and its halogen substitution products, have critical constants agreeing with this originally empirical law, due to Sydney Young and Thomas; acetic acid behaves abnormally, pointing to associated molecules at the critical point.

    66

    By means of the spectroscope it is possible to determine the relative orbital velocity of the two components, and this when compared with the period fixes the absolute dimensions of the orbit; the apparent dimensions of the orbit being known from visual observations the distance can then be found.

    67

    By order of the Russian government, he visited each of the great tea-growing countries, and the results of his observations were published in a book entitled On the Tea-producing Districts of Asia.

    68

    By subsequent journeys in Hungary, Transylvania, Italy, Sicily, France and Germany he extended his knowledge of volcanic phenomena; and in 1826 the results of his observations were given in a work entitled A Description of Active and Extinct Volcanos (2nd ed., 1848).

    69

    By the adoption of a regular system of work, and a careful plan of reduction, he was able to keep his observations reduced practically up to date, and published them annually with a degree of punctuality which astonished his contemporaries.

    70

    By way of examples of L'Herminier's observations, what he says of the two groups that had been the subject of Cuvier's and the elder Geoff roy's contest may be mentioned.

    71

    C. C. Baly (21), making use of the observations of the Russian expedition in Spitsbergen in 1899, accepts as the wave-lengths of the three principal auroral lines 557 o, 4276 and 3912; and he identifies all three and ten other auroral lines ranging between 5570 and 3707 with krypton lines measured by himself.

    72

    Callendar finds that five molecules of water in the case of cane-sugar or two molecules in the case of dextrose are required to bring the curves into conformity with the observations of Berkeley and Hartley, which in fig.

    73

    Carrying on the work from the anatomical point at which he had left it, correcting his errors, and utilizing to the fullest extent the observations of Keyserling and Blasius, to which reference has already been made, Muller, though hampered by mistaken notions of which he seems to have been unable to rid himself, propounded a scheme for the classification of this group, the general truth of which has been admitted by all his successors, based, as the title of his treatise expressed, on the hitherto unknown different types of the vocal organs in the Passerines.

    74

    Climatological Atlas of the Russian Empire, by the Physical Observatory (St Petersburg, 1900), gives data and observations covering the period 1849-1899.

    75

    Comparatively Simple Formulae, Therefore, Suffice For Its Expression To 1 In 10,000, Which Is Beyond The Limits Of Accuracy Of The Observations.

    76

    Considering the accuracy of these measures (an accuracy far surpassing that of any other contemporary observations), it is somewhat surprising that this form of micrometer was never systematically used in any sustained or important astronomical researches, although a number of instruments of the kind were made by Dollond.

    77

    Ctesibius of Alexandria, Hero and others, founded the science of pneumatics on observations on the physical properties of air.

    78

    Cuvier seems to have acquiesced in the corrections of his views made by Geoffroy, and attempted no rejoinder; but the attentive and impartial student of the discussion will see that a good deal was really wanting to make the latter's reply effective, though, as events have shown, the former was hasty in the conclusions at which he arrived, having trusted too much to the first appearance of centres of ossification, for, had his observations in regard to other birds been carried on with the same attention to detail as in regard to the fowl, he would certainly have reached some very different results.

    79

    Direct material for answering the question when and how far astronomical calculations replaced simple observations as the basis of the Jewish calendar is not forthcoming.

    80

    Direct observations of currents in the open sea are difficult, and even when the ship is anchored the veering and rolling of the vessel produce disturbances that greatly affect the result.

    81

    Dr Warton, in his observations upon Pope's line, "Unthought-of frailties cheat us in the wise," says, "Who could imagine that Locke was fond of romances; that Newton once studied astrology; that Dr Clarke valued himself on his agility, and frequently amused himself in a private room of his house in leaping over the tables and chairs ?"

    82

    Dumas went no further that thus epitomizing his observations; and the next development was made in 1836 by Auguste Laurent, who, having amplified and discussed the applicability of Dumas' views, promulgated his Nucleus Theory, which assumed the existence of " original nuclei or radicals " (radicaux or noyaux fondamentaux) composed of carbon and hydrogen, and " derived nuclei " (radicaux or noyaux derives) formed from the original nuclei by the substitution of hydrogen or the addition of other elements, and having properties closely related to the primary nuclei.

    83

    During an attack of fever he made observations on himself with reference to the action of quickened circulation upon thought, which led him to the conclusion that psychical phenomena were to be accounted for as the effects of organic changes in the brain and nervous system.

    84

    During his tenure of the latter chair he distinguished himself by observations on the lymphatics.

    85

    During Nansen's expedition on the " Fram " in 1894-1895, Scott Hansen made observations with a Sterneck's half-seconds pendulum on the ice where the sea was more than 1600 fathoms deep and found only an insignificant deviation from the number of swings corresponding to a normal ellipsoid.

    86

    Early in life Feltham visited Flanders, and published observations in 1652 under the title of A Brief Character of the Low Countries.

    87

    Early in life he published observations on the Tertiary and Post-Tertiary deposits in the Thames valley, and on fossil plants and various invertebrata, in the Magazine of Natural History, the Annals of Nat.

    88

    Even this correction is not sufficient in solution of sugar, where the theoretical curve II lies below the experimental observations.

    89

    Every once in a while, the half-demon surprised him with the depth of his observations and compassion.

    90

    Experiments and Observations on Electricity (London, 1769) was translated into French by Barbeu Dubourg (Paris, 1773); Vaughan attempted a more complete edition, Political, Miscellaneous and Philosophical Pieces (London, 1 779); an edition in three volumes appeared after Franklin's death (London, 1806); what seemed the authentic Works, as it was under the care of Temple Franklin, was published at London (6 vols., 1817-1819; 3 vols., 1818) and with some additional matter at Philadelphia (6 vols., 1818).

    91

    Following the first chart of lines of equal variation compiled by Edmund Halley in 1700, charts of similar type have been published from time to time embodying recent observations and corrected for the secular change, thus providing seamen with values of the variation accurate to about 30' of arc. Possessing these data, it is easy to ascertain by observation the effects of the iron in a ship in disturbing the compass, and it will be found for the most part in every vessel that the needle is deflected from the magnetic meridian by a horizontal angle called the deviation of the compass; in some directions of the ship's head adding to the known variation of the place, in other directions subtracting from it.

    92

    For a description of the method of using the Fox circle for observations at sea consult the Admiralty Manual of Scientific Inquiry, p. 116, while a description of the most recent form of the circle, known as the Lloyd-Creak pattern, will be found in Terrestrial Magnetism, 1901, 6, p. 119.

    93

    For the statement of the motions of these bodies uniform motion in a circle was employed as a fundamental type, combinations of motions of this type being constructed to fit the observations.

    94

    For these reasons the coelostat is never likely to be largely employed in general astronomical work, but it is admirably adapted for spectroscopic and bolometric observations of the sun, and for use in eclipse expeditions.

    95

    For this purpose he repaired to the Rectory, Wanstead, then the residence of Mrs Pound, the widow of his uncle James Pound, with whom he had made many observations of the heavenly bodies.

    96

    For this reason observations at different depths in the same locality often give very concordant results for the same period, as the total percolation and the average rate are necessarily nearly the same for the various strata, although the actual degree of wetness of each may vary considerably.

    97

    Forbes was also interested in geology, and published memoirs on the thermal springs of the Pyrenees, on the extinct volcanoes of the Vivarais (Ardeche), on the geology of the Cuchullin and Eildon hills, &c. In addition to about 150 scientific papers, he wrote Travels through the Alps of Savoy and Other Parts of the Pennine Chain, with Observations on the Phenomena of Glaciers (1843); Norway and its Glaciers (1853); Occasional Papers on the Theory of Glaciers (1859); A Tour of Mont Blanc and Monte Rosa (1855).

    98

    Formerly attempts were made to determine parallaxes by measuring changes in the absolute right ascensions and declinations of the stars from observations with the meridian circle.

    99

    From 1881 till 1904 meteorological observations were taken from the summit of Ben Nevis, the observers at first making the ascent daily for the purpose.

    100

    From an investigation of all the observations upon Mercury and the other three interior planets, Simon Newcomb found it almost out of the question that any such mass of matter could exist without changing either the figure of the sun itself or the motion of the planes of the orbits of either Mercury or Venus.

    101

    From observations made at Sana by Manzoni, Defiers and Glaser, the mean temperature for the year of that city at an altitude of 7300 ft.

    102

    From the analogy of the higher plants observers have justly argued that when they have seen and marked the characters of the reproductive organs they have found the plant at the stage when it exhibits its most noteworthy features, and they have named and classified the species in accordance with these observations.

    103

    From the few observations that exist, it seems that farther south the southern winter winds decrease rapidly, becoming westerly, until at Assuan and Wadi Haifa the northerly winds are almost invariable throughout the year.

    104

    From the meridian observations of the same planets made for the purpose of controlling the elements of motion of the planets Auwers found it = 8.806".

    105

    From these observations he drew the natural conclusion that the spermatium was a male, sexual cell.

    106

    From this equation the osmotic pressure Po required to keep a solution in equilibrium as regards its vapour and through a semi-permeable membrane with its solvent, when that solvent is under its own vapour pressure, may be calculated from the results of observations on vapour pressure of solvent and solution at ordinary low hydrostatic pressures.

    107

    Further, we know that in the 8th century B.C., there were observatories in most of the large cities in the valley of the Euphrates, and that professional astronomers regularly took observations of the heavens, copies of which were sent to the king of Assyria; and from a cuneiform inscription found in the palace of Sennacherib at Nineveh, the text of which is given by George Smith,5 we learn that at that time the epochs of eclipses of both sun and moon were predicted as possible - probably by means of the cycle of 223 lunations or Chaldaean Saros - and that observations were made accordingly.

    108

    Furthermore, the observations on American wasps render it probable that the earlier accounts of the instinctive behaviour of such wasps are exaggerated.

    109

    Gears are provided for elevating, levelling, aligning the upper and lower optical systems, adjusting the inclination of the reflector and rotating the mast around a vertical axis so that observations may be made and azimuth angles taken in all directions.

    110

    Given that such observations at the surface of the sea, at intermediate levels and at the bottom are sufficiently numerous and are of a high degree of precision, general conclusions as to the movements of the ocean may be deduced from established theorems in hydrodynamics.

    111

    Gockel, have made long series of observations without it.

    112

    Having obtained pecuniary assistance from the Danish government, he travelled through all Iceland for scientific purposes in the years 1837-1842, and made many interesting geological observations.

    113

    He accepted also the division into five zones; he quotes approvingly the assertion of Hipparchus that it was impossible to make real advances in geography without astronomical observations for determining latitudes and longitudes.

    114

    He also determined the mass of the moon, and from a discussion of the Greenwich transit circle observations between 1851 and 1865 he found for the constant of nutation the value 9.134".

    115

    He also edited Coeli et siderum in eo errantium observationes Hassiacae (1618), containing the astronomical observations of Landgrave William IV.

    116

    He also made observations on the flight of rockets, and wrote on the advantages of rifled barrels.

    117

    He also reduced the solar parallax to 14" (less than a quarter of Kepler's estimate), corrected the sun's semi-diameter to 15' 45", recommended decimal notation, and was the first to make tidal observations.

    118

    He arranges a selection from his observations on the nebulae in such a way as to give great plausibility to his view of the gradual transmutation of nebulae into stars Herschel begins by showing us that there are regions in the heavens where a faint diffused nebulosity is all that can be detected by the telescope.

    119

    He became intimate with James Bradley in 1755, and in 1761 was deputed by the Royal Society to make observations of the transit of Venus at St Helena.

    120

    He calculated an orbit for the comet of 1 759 (Halley's), reduced Lacaille's observations of 515 zodiacal stars, and was, in 1763, elected a member of the Academy of Sciences.

    121

    He established an astronomical observatory at Paramatta in 1822, and the Brisbane Catalogue, which was printed in 1835 and contained 7385 stars, was the result of observations made there in 1822-1826.

    122

    He founded the Sidereal Messenger in 1846, was one of the first to adopt (in 1848) the electrical method of recording observations, and published besides other works, The Orbs of Heaven (1848, &c.), and Popular Astronomy (1860), both reissued at London in 1892.

    123

    He further induced the government to print his observations annually, thereby securing the prompt dissemination of a large mass of data inestimable from their continuity and accuracy.

    124

    He had from the first been strongly opposed to the war, and in 1776 he published a pamphlet entitled Observations on Civil Liberty and the Justice and Policy of the War with America.

    125

    He is best known by the five volumes of Medical Inquiries and Observations, which he brought out 'at intervals from 1789 to 1798 (two later editions revised by the author).

    126

    He made a great number of observations of stars with proper motion.

    127

    He moreover accuses Eratosthenes, (whose determination of a degree he accepts without hesitation) with trusting too much to hypothesis in compiling his map instead of having recourse to latitudes and longitudes deduced by astronomical observations.

    128

    He notes the convenience of the method for solar observations and its previous use by some of the observers already mentioned, as well as its advantages for easily and accurately copying on an enlarged or reduced scale, especially for chorographical or topographical documents.

    129

    He now fixed his residence at Islington, engaged chiefly upon lunar observations, with a view to the great desideratum of a method of finding the longitude at sea.

    130

    He organised extensive magnetical and meteorological observations, and in 1839 he started regular observations of the periodical phenomena of vegetation, especially the flowering of plants.

    131

    He remodelled the volumes of observations, put the library on a proper footing, mounted the new (Sheepshanks) equatorial and organized a new magnetic observatory.

    132

    He shared and defended many of Sydenham's principles, and in the few medical observations he has left shows himself to be even more thorough-going than the "English Hippocrates."

    133

    He started once more in December 1771, and at length reached the Coppermine river, which he surveyed to its mouth, but his observations are unreliable.

    134

    He was especially interested in questions relating to the polarization of light, and his observations in this field, which gained him the Rumford medal of the Royal Society in 1840, laid the foundations of the polarimetric analysis of sugar.

    135

    He was the first correctly to solve Aristotle's problem, stated above, and to apply it practically to solar observations in a darkened room (Cosmographia, 1 535).

    136

    He was the first to employ mercury for the air-pump, and devised a method of determining longitude at sea by observations of the moon among the stars.

    137

    He wrote Personal Recollections (1896), Military Europe (1898) and Observations Abroad (1899).

    138

    Heliometer observations of distance in their most refined sense cannot be considered absolute measures of angles.

    139

    Hence his work, written in French, contains a far greater amount of original matter; and his personal observations made in many countries, from England to Egypt, enabled him to avoid most of the puerilities which disfigure other works of his own or of a preceding age.

    140

    Hence in more recent patterns of magnetometer it is usual to do away with the transit mirror method of observing and either to use a separate theodolite to observe the azimuth of some distant object, which will then act as a fixed mark when making the declination observations, or to attach to the magnetometer an altitude telescope and circle for use when determining the geographical meridian.

    141

    Hence, from the two observations the value of the earth's total force can be deduced.

    142

    His best work, the Valesiana (1694), was inspired by filial affection; in it he collected a number of historical and critical observations, anecdotes and Latin poems of his father.

    143

    His careful observations concerning the meteorology of this region are of great value, and his surveys between Kopa and the' Naichi Gol were in a country not previously explored.

    144

    His chapter on the flea, in which he not only describes its structure, but traces out the whole history of its metamorphoses from its first emergence from the egg, is full of interest - not so much for the exactness of his observations, as for its incidental revelation of the extraordinary ignorance then prevalent in regard to the origin and propagation of "this minute and despised creature," which some asserted to be produced from sand, others from dust, others from the dung of pigeons, and others from urine, but which he showed to be "endowed with as great perfection in its kind as any large animal," and proved to breed in the regular way of winged insects.

    145

    His chief books on chemistry were six volumes of Experiments and Observations on different Kinds of Air, published between 1774 and 1786; Experiments on the Generation of Air from Water (1793) Experiments and Observations relating to the Analysis of Atmospheric Air, and Considerations on the Doctrine of Phlogiston established and that of the Composition of Water refuted (1800).

    146

    His detection of considerable errors in the tables then in use led him to the conclusion that a more accurate ascertainment of the places of the fixed stars was indispensable to the progress of astronomy; and, finding that Flamsteed and Hevelius had already undertaken to catalogue those visible in northern latitudes, he assumed to himself the task of making observations in the southern hemisphere.

    147

    His first separate publication was Meteorological Observations and Essays (1793), which contained the germs of several of his later discoveries; but in spite of the originality of its matter, the book met with only a limited sale.

    148

    His first task on taking up this post was the reduction and publication of a large mass of observations left by his predecessor, from a selected portion of which (those made 1856-1860) he compiled a catalogue of 1154 stars.

    149

    His mind was as well cultivated as his bodily powers; he wrote well, and his observations are generally acute and accurate; he was brave, kindly and generous.

    150

    His name is chiefly known for his mineralogical observations and for his work on soluble glass.

    151

    His observations appeared in four large folio volumes (1776-1811).

    152

    His observations led him to the view that a glacier is an imperfect fluid or a viscous body which is urged down slopes of a certain inclination by the mutual pressure of its parts, and involved him in some controversy with Tyndall and others both as to priority and to scientific principle.

    153

    His observations of the great comet of January 1672 supplied the basis of modern cometary astronomy.

    154

    His observations of the protuberances on the sun, made during the total eclipse on the 10th of July 1860, are included in the work of Madler on the eclipse, published in 1861.

    155

    His observations on the three comets of 1618 were published in De Cometis, contemporaneously with De Harmonice Mundi (Augsburg, 1619), of which the first lineaments had been traced twenty years previously at Gratz.

    156

    His observations showed that the osmotic pressure was nearly proportional to the concentration and to the absolute temperature over a limited range.

    157

    His principal observations are given in his work, Experimenta nova, ut vocant, Magdeburgica de vacuo spatio (Amsterdam, 1672).

    158

    His remarks on horses, cattle, &c., are not less interesting; and there is a very good account of the diseases of each species, and some just observations on the advantage of mixing different kinds on the same pasture.

    159

    His result, from his observations alone, was 20.52"; and taking into account the other Puikowa results, he concluded the most probable value to be 20.492".

    160

    His Tibetische Studien (1851-1868) is a valuable collection of documents and observations.

    161

    His true greatness can only be estimated by a consideration of the fact that he was a great teacher not only of human and comparative anatomy and zoology but also of physiology, and that nearly all the most distinguished German zoologists and physiologists of the period 1850 to 1870 were his pupils and acknowledged his leadership. The most striking feature about Johann Miller's work, apart from the comprehensiveness of his point of view, in which he added to the anatomical and morphological ideas of Cuvier a consideration of physiology, embryology and microscopic structure, was the extraordinary accuracy, facility and completeness of his recorded observations.

    162

    His university career lasted three years, and on its termination he became a tutor at Toxteth, devoting to astronomical observations his brief intervals of leisure.

    163

    His work also included observations on putrefaction and fermentation, which he spoke of as sisters, on the nature of salts, and on the preparation of pure metals.

    164

    His work, entitled Observations on the Diseases of an Army, was translated into many European languages and became the standard authority on the subject.

    165

    His works contain, however, many original experiments, and excellent practical observations.

    166

    History had always been a favourite study with him, and Mably's Observations sur l'histoire appears to have had considerable influence in determining him to the choice of some special period for historic research.

    167

    Hoffer's observations, it seems that the femalePsithyrus builds her own cells.

    168

    Hooke, in 1674, published his observations of y Draconis, a star of the second magnitude which passes practically overhead in the latitude of London, and whose observations are therefore singularly free from the complex corrections due to astronomical refraction, and concluded that this star was 23" more northerly in July than in October.

    169

    How the change from the autumnal to the winter condition takes place appears not to be definitely settled in all cases, and accurate observations are much to be desired.

    170

    Huc was, indeed, not only without science, perhaps without accurate knowledge of any kind, but also without that geographical sense which sometimes enables a traveller to bring back valuable contributions to geographical knowledge though unable to make instrumental observations.

    171

    If an auroral arc represented a definite selfluminous portion of space of small transverse dimensions at a uniform height above the ground, its height could be accurately determined by observations made with theodolites at the two ends of a measured base, provided the base were not too short compared to the height.

    172

    If the Godthaab observations can be trusted, auroral discharges must often occur within a few miles of the earth's surface in Arctic regions.

    173

    Important magnetic observations were begun at Makerstoun in 1841, and the results gained him in 1848 the Keith prize of the Royal Society of Edinburgh, in whose Transactions they were published.

    174

    In 1611 Johann Fabricius published his observations of sun-spots and describes how he and his father fell back upon the old method of projecting the sun's image in a darkened room, finding that they could observe the spots just as well as with the telescope.

    175

    In 1639 he accompanied Pedro Texiera in his second exploration of the Amazon, in order to take scientific observations, and draw up a report for the Spanish government.

    176

    In 1680 Jean Picard, in his Voyage d'Uranibourg, stated, as a result of ten years' observations, that Polaris, or the Pole Star, exhibited variations in its position amounting to 40" annually; some astronomers endeavoured to explain this by parallax, but these attempts were futile, for the motion was at variance with that which parallax would occasion.

    177

    In 1696 he was, although a zealous Tory, appointed deputy comptroller of the mint at Chester, and (August 19, 1698) he received a commission as captain of the "Paramour Pink" for the purpose of making extensive observations on the conditions of terrestrial magnetism.

    178

    In 1752 he published an Essai d'une nouvelle theorie sur la resistance des / g uides, which contains a large number of original ideas and new observations.

    179

    In 1755 he submitted to the English government an amended body of MS. tables, which James Bradley compared with the Greenwich observations, and found to be sufficiently accurate to determine the moon's place to 75", and consequently the longitude at sea to about half a degree.

    180

    In 1769, in a letter to Dr Franklin, he wrote some observations on the expectation of lives, the increase of mankind, and the population of London, which were published in the Philosophical Transactions of that year; in May 1770 he communicated to the Royal Society a paper on the proper method of calculating the values of contingent reversions.

    181

    In 1776 appeared his (anonymous) pamphlet on the American revolution in opposition to Dr Price's Observations on the Nature of Civil Liberty, in which he sympathized with the views of the British legislature.

    182

    In 1776 it was moved in the House of Commons by David Hartley, son of the author of Observations on Man, that " the slave trade was contrary to the laws of God and the rights of men "; but this motion - the first which was made on the subject - failed.

    183

    In 1797 she presented to the Royal Society an Index to Flamsteed's observations, together with a catalogue of 561 stars accidentally omitted from the "British Catalogue," and a list of the errata in that publication.

    184

    In 1807 an account of the magnetic observations made during the tour with Humboldt was published in the first volume of the Memoires d'Arcueil, and the second volume, published in 1809, contained the important memoir on gaseous combination (read to the Societe Philomathique on the last day of 1808), in which he pointed out that gases combining with each other in volume do so in the simplest proportions-1 to 1, 1 to 2, 1 to 3 - and that the volume of the compound formed bears a simple ratio to that of the constituents.

    185

    In 1829-1830 he published his Lehrbuch der Chemie, which embodied many original observations.

    186

    In 1847 an altazimuth was erected, designed by Airy to enable observations of the moon to be made not only on the meridian, but whenever she might be visible.

    187

    In 1862 he received the gold medal of the latter society, and in 1864 a Royal medal from the Royal Society, for his observations on the total eclipse of the sun in 1860, and for his improvements in astronomical photography.

    188

    In 1865 De Bary suggested the possibility that such lichens as Collema, Ephebe, &c., arose as a result of the attack of parasitic Ascomycetes upon the algae, Nostoc, Chroococcus, &c. In 1867 the observations of Famintzin and Baranetzky showed that the gonidia, in certain cases, were able to live outside the lichen-thallus, and in the case of Physcia, Evernia and Cladonia were able to form zoospores.

    189

    In 1885 Messrs Garde and Eherlin made similar observations at Nanortalik near Cape Farewell in Greenland, but using a base of only 1250 metres (about 4 m.).

    190

    In 1895 Chandler, from a general discussion of all the observations, derived the value of 20.50".

    191

    In a refined form this method is often employed for measuring the intensity of a magnetic field at a given place, just as the intensity of gravity at different parts of the earth is deduced from observations of the rate at which a pendulum of known length vibrates.

    192

    In a series of observations of winds about one half have been found to indicate a direction from north-east or east.

    193

    In a year and a half the cubs attain their full development; and from observations on captive specimens it appears that the duration of life ought to extend to some thirteen or fourteen years.

    194

    In addition, taking advantage of the accuracy with which the bolometer can determine the position of a source of heat by which it is affected, he mapped out in this infra-red spectrum over 700 dark lines or bands resembling the Fraunhofer lines of the visible spectrum, with a probable accuracy equal to that of refined astronomical observations.

    195

    In another respect the observations of Fraunhofer appear at first sight to be in disaccord with theory; for his measures of the diameters of the red rings, visible when white light was employed, correspond with the law applicable to dark rings, and not to the different law applicable to the luminous maxima.

    196

    In biological chemistry he worked at the problems of animal heat and at the phenomena accompanying the growth of plants, and he also devoted much time to meteorological questions and observations.

    197

    In Clausilia, according to the observations of C. Gegenbaur, the primitive shell-sac does not flatten out and disappear, but takes the form of a flattened closed sac. Within this closed sac a plate of calcareous matter is developed, and after a time the upper wall of the sac disappears, and the calcareous plate continues to grow as the nucleus of the permanent shell.

    198

    In each case the results of the observations may be systematically in error, not only from the uncertain diameter of the moon, but in a still greater degree from the varying effect of irradiation and the personal equation of the observers.

    199

    In England all the barons or greater nobility were entitled to bear banners, and therefore Du Cange's observations would apply to them as well as to the barons or greater nobility of France and Spain.

    200

    In his Statical Essays (1727) he gave an account of numerous experiments and observations which he had made on the nutrition of plants and the movement of sap in them.

    201

    In observations of position angle one of the two tablets 81 can be used to record the readings.

    202

    In order to obtain the declination a pivoted magnet is used to obtain the magnetic meridian, the geographical meridian being obtained by observations on the sun or stars.

    203

    In order to select remedies which should fulfil the indication of producing symptoms like those of the disease, Hahnemann made many observations of the action of drugs on healthy persons.

    204

    In practice it is found that a magnet can be prepared which, when suitably protected from shock, &c., retains its magnetic moment sufficiently constant to enable observations of H to be made comparable in accuracy with that of the other elements obtained by the instruments ordinarily employed at sea.

    205

    In recent times, especially since the rapid increase in the study of the exact sciences during the 19th century, observations at sea with accurate instruments have become common, and the ships' logs of to-day are provided with headings for entering daily observations of the phenomena of the seasurface.

    206

    In the absence of such a reversible card the index correction must be determined by comparison with a unifilar magnetometer, simultaneous observations being made on shore, and these observations repeated as often as occasion permits.

    207

    In the British Isles the 1 The name of the fishes of the genus Cyprinus is derived from the island of Cyprus, the ancient sanctuary of Venus; this name is supposed to have arisen from observations of the fecundity and vivacity of carp during the spawning period.

    208

    In the electrical method, observations of the variable flow are useful for finding the value of c for the specimen, but are not otherwise required.

    209

    In the evolution of these laws Dr Cornay had most laudably studied, as his observations prove, a vast number of different types, and the upshot of his whole labours, though not very clearly stated, was such as to wholly subvert the classification at that time generally adopted by French ornithologists.

    210

    In the island of Juist, off the Friesland coast, from three weeks' observations they obtained only 5.2 as the mean.

    211

    In the latter case, being determined by observations of the sun, it is taken to begin with the passage of the mean sun over the meridian of the place, or at mean noon, while the civil day begins at midnight.

    212

    In the meantime some confirmation of the law has been obtained from terrestrial experiments, and observations of double stars tend to indicate for it a wider if not universal range.

    213

    In the myelinated cell branches of the neuron, that is, in the ordinary nerve fibres, no visible change has ever been demonstrated as the result of any normal activity, however great - a striking contrast to the observations obtained on the perikarya.

    214

    In the Observations sur les ecrits modernes (1735-1743) Desfontaines held the gates of Philistia for eight years against the Encyclopaedists, and even the redoubtable Voltaire himself.

    215

    In the skysearching periscope the upper prism can be rotated by mechanism inside the periscope, so that aerial observations can be readily made before the submarine " breaks surface."

    216

    In the very earliest submarines a cupola was built on the top of the hull, which was kept just above the surface when it was desired to take observations.

    217

    In this attempt he was unsuccessful, but the observations he made in the course of his experiments induced him, early in 1856, to try the effect of treating aniline sulphate with bichromate of potash.

    218

    In this theory there can strictly be no "causation"; one thing is observed to succeed another, but observations cannot assert that it is "caused" by that thing; it is post hoc, but not propter hoc. The idea of necessary connexion is a purely mental idea, an a priori conception, in which observation of empirical data takes no part; empiricism in ethics likewise does away with the idea of the absolute authority of the moral law as conceived by the intuitionalists.

    219

    Interpolation is easy in the case of all observations taken with a grating.

    220

    Ire these methods the flow of heat is deduced from observations of the rate of change of temperature with time in a body exposed to known external or boundary conditions.

    221

    Isomorphism is most clearly discerned between elements of analogous chemical properties; and from the wide generality of such observations attempts have been made to form a classification of elements based on isomorphous replacements.

    222

    It follows that for observations in which light is a consideration spectroscopes should be used which give about twice the resolving power of that actually required; we may then use a slit having a width of nearly eight times that of the normal one.

    223

    It had been supposed that, with the greatly improved telescopes of modern times, contact observations could be made with much greater precision than in 1761 and 1769, yet, for some reason which it is not easy to explain completely, the modern observations were but little better than the older ones.

    224

    It has been abundantly demonstrated by careful observations that the east coasts of Japan are slowly rising.

    225

    It has been maintained that this tendency to a severance of the hybrid stock into its components must favour the persistence of a new character of large volume suddenly appearing in a stock, and the observations of Mendel have been held to favour in this way the views of those who hold that the variations upon which natural selection has acted in the production of new species are not small variations but large and " discontinuous."

    226

    It has been pointed out that the cavity of the sacs corresponds in many particulars with the coelom of higher animals, and in Lebidinsky's observations on the development there is some support to the view that a coelom exists.

    227

    It is a problem how to reconcile his ignorance, his weakness, his superstition, his crude notions, his erroneous observations, his ridiculous influences and theories, with his grasp of method, his lofty views of the true scope of medicine, his lucid statements, his incisive and epigrammatic criticisms of men and motives.

    228

    It is believed to have been in use from the very time of its origin; for the observations of eclipses which were collected in Chaldaea by Callisthenes, the general of Alexander, and transmitted by him to Aristotle, were for the greater part referred to the beginning of the reign of Nabonassar, founder of the kingdom of the Babylonians.

    229

    It is convenient to give this calculation before proceeding to describe the experimental determination of the velocity in air, in other gases and in water, since the calculation serves to some extent as a guide in conducting and interpreting the observations.

    230

    It is important as having been adopted by Regnault (and also by many subsequent calculators) for the expression of his observations on the vapour-pressures of steam and various other substances.

    231

    It is one of Darwin's great merits to have made use of these observations and to have formulated their results to a large extent as the laws of variation and heredity.

    232

    It is probable for this reason that the average conductivity of the earth's crust, as deduced from surface observations, is too large; and that estimates of the age of the earth based on such measurements are too low, and require to be raised; they would thereby be brought into better agreement with the conclusions of geologists derived from other lines of argument.

    233

    It is probable that the first collection of astronomical observations and terrestrial omens was made for a library established by Sargon.

    234

    It is probable, however, that the above observations may 1 Phys.

    235

    It is remarkable that the discussion of ancient eclipses of the moon, and their comparison with modern observations, show only a small and rather doubtful change, amounting perhaps to less than one-hundredth of a second per century.

    236

    It is so called in memory of Idris Gawr, celebrated in the Triads as one of the three "Gwyn Serenyddion," or "Happy Astronomers," of Wales, who is traditionally supposed to have made his observations on this peak.

    237

    It is therefore necessary to train the periscope round when taking observations on different bearings.

    238

    It is thought better here, for the sake of clearness, to reserve observations on revenues specially assigned to the international administration of the Ottoman Public Debt, and on the expenditure of that administration, and to deal with that subject separately, while, however, including the total figures of both in the general figures in order to reproduce exactly the totals shown in the budget of the empire.

    239

    It is true that in 1823 Fraunhofer, inspired by his observations upon gratings, had very nearly hit the mark.'

    240

    It never occurred to me that it might be worth while to make my own observations and describe the experiences peculiarly my own.

    241

    It should be noticed that the verification was begun without any data as to the masses of the celestial bodies, these being selected and adjusted to fit the observations.

    242

    It was the brilliant exhibition in November 1833 that, in modern times particularly, attracted earnest students to investigate the subject of meteors generally, and to make systematic observations of their apparitions on ordinary nights of the year.

    243

    It would hardly be safe to generalize from these observations; the effects may possibly be dependent upon the physical condition of the metals.

    244

    Klebs has, however, recently canvassed the conclusions of both these investigators; and as the result of his own observations declares that algae, so far from being as polymorphic as they have been described, vary only within relatively narrow limits, and present on the whole as great fixity as the higher plants.

    245

    Kopp systematized the earlier observations, and, having made many others, he was able to show that the molecular heat was an additive property, i.e.

    246

    Laplace is due the theoretical proof that this function is independent of temperature and pressure, and apparent experimental confirmation was provided by Biot and Arago's, and by Dulong's observations on gases and vapours.

    247

    Like Horace he largely illustrated his own observations by personal anecdotes and fables.

    248

    Little is known of the ministry of Angad except that he committed to writing much of what he had heard about Guru Nanak as well as some devotional observations of his own, which were afterwards incorporated in the Granth.

    249

    Lyell marshalled all the observations he could collect in support of this principle, teaching that the present is the key to the past, and arraying all obtainable evidence against the cataclysmic theories of Cuvier.

    250

    Magnetization In Very Weak Fields Some interesting, observations have been made of the effects produced by very small magnetic forces.

    251

    Many periscopes of considerable length and special design have been used, to enable observations being made in comparative safety from behind large objects, e.g.

    252

    Mendel's observations constitute an ingenious attempt to throw light on the matter, and in the opinion of some biologists have led to the discovery of an important principle.

    253

    Mention should also be made of a third method which has hardly yet been tried, namely, that of endeavouring to isolate one of the three "directions" by the method of suggestion or even hypnotic trance observations.

    254

    Meridian observations of the moon have been heretofore made by observing the transit of its illuminated limb.

    255

    Meteorological statistics are collected at Auckland, Wellington, Christchurch, and Dunedin and eight other stations; and observations of rainfall, temperature, and wind-directions are received from eighteen stations of the second class.

    256

    Meyer's observations, they attain a length of from 17 to 18 mm.

    257

    Mill has shown that in the North Sea off the Firth of Forth the average depth of visibility of a disk in the winter half-year was 4; fathoms and in the summer half-year 62 fathoms, and, although the greater frequency of rough weather in winter might tend to obscure the effect, individual observations made it plain that the angle of the sun was the main factor in increasing the depth to which the disk remained visible.

    258

    Moestlin and his pupil Kepler - the latter applying it in 1607 to the observation of a transit of Mercury - also by Johann Fabricius, in 1611, for the first observations of sun-spots.

    259

    More important are Kekule's observations that nitrous acid oxidizes pyrocatechol or [I.2]-dioxybenzene, and protocatechuic acid or [3.4]- dioxybenzoic acid to dioxytartaric acid, (C(OH) 2 COOH) 2 (Ann., 1883, 221, p. 230); and 0.

    260

    More than a thousand observations in duplicate have been made of the paths of identical meteors seen from two stations many miles apart.

    261

    Morris's results for iron, and gives some additional observations for steel, nickel and cobalt.

    262

    Most of the birds he describes are characterized with accuracy sufficient to enable them to be identified, and his observations upon them have still some interest; but he was innocent of any methodical system, and was not exempt from most of the professional fallacies of his time.'

    263

    Most of the mechanical contrivances which made Tycho Brahe's instruments so superior to those of his contemporaries were adopted at Cassel about 1584, and from that time the observations made there seem to have been about as accurate as Tycho's; but the resulting longitudes were 6' too great in consequence of the adopted solar parallax of 3'.

    264

    Nearly every one of the modern instruments used for the observations of physical astronomy is a part of the perfected astrolabe.

    265

    Neumann, who, in 1831, deduced from observations on many carbonates (calcium, magnesium, ferrous, zinc, barium and lead) that stoichiometric quantities (equimolecular weights) of compounds possess the same heat capacity.

    266

    Nevertheless he believes that, when we can apply measures to the combination of empirical appearances, then we can apply the logical principle as causal law to this combination, and say that one appearance is the cause of another, thus adding a notion of causality not contained in the actual observations, but specializing the general notion of causality.

    267

    Newton accepted the three subclasses of Huxley, Saururae, Ratitae and Carinitae, and made a series of cautious but critical observations on the minor divisions of the Carinates.

    268

    Nilson and Pettersson's observations on beryllium and germanium have shown that the atomic heats of these metals increase with rise of temperature, finally becoming constant with a value 5.6.

    269

    No adequate investigation of this subject has yet been made, but some observations made by the author of this article, on the piebald black and white rat, show that differences connected with the microscopic structure exist.

    270

    No aid to the trained eye was necessary for such observations, and for many other such; yet, if we take Sir Thomas Watson (1792-1882) as a modern Sydenham, we may find in his lectures no suspicion that there may be a palsy of muscular co-ordination apart from deprivation of strength.

    271

    No biological generalization rests on a wider series of observations, or has been subjected to a more critical scrutiny than that every living organism has come into existence from a living portion or portions of a pre-existing organism.

    272

    No calorimetric observations are required, but the results are obtained in terms of the thermal capacity of unit volume c, and the measurements give the diffusivity klc, instead of the calorimetric conductivity k.

    273

    No purely astronomical enterprise was ever carried out on so Transits of P large a scale or at so great an expenditure of money and labour as was devoted to the observations of these transits, and for several years before their occurrence the astronomers of every leading nation were busy in discussing methods of observation and working out the multifarious details necessary to their successful application.

    274

    No serious observer, acquainted with modern microscopic technical methods, has been able to confirm the explanation of their observations.

    275

    Norden's work contains many judicious observations on the " different natures of grounds, how they may be employed, how they may be bettered, reformed and amended."

    276

    Nothing is said about the use of a lens or of solar observations.

    277

    Oberlin published several manuals on archaeology and ancient geography, and made frequent excursions into different provinces of France to investigate antiquarian remains and study provincial dialects, the result appearing in Essai sur le patois Lorrain (1775); Dissertations sur les Minnesingers (1782-1789); and Observations concernant le patois et les mceurs des gens de la campagne (1791).

    278

    Observations have shown that, in addition to the comparatively great and sudden displacements which occur in earthquakes, the ground is subject to other movements.

    279

    Observations have usually been limited to a portion of the year, or to a few hours of the day, whilst the results from different stations differ much in details.

    280

    Observations in temperature and salinity have only been taken during summer.

    281

    Observations made at the most diverse parts of the globe, and the general distribution area of the disease, show that mere questions of elevation, or even configuration of the ground, have little or no influence.

    282

    Observations on birds form the principal though by no means the whole theme of this book, which may be safely said to have done more to promote a love of ornithology in England than any other work that has been written, nay more than all the other works (except one next to be mentioned) put together.

    283

    Observations on the Sonnblick agree with those at low-level stations in showing a diminution of dissipation with increase of relative humidity.

    284

    Observations undertaken mainly in the interest of Prout's law, and extending over many years, had been conducted to determine afresh the densities of the principal gases - hydrogen, oxygen and nitrogen.

    285

    Observations were made on a ring in a pine-wood for a period of nine years, and it was calculated that it increased from centre to circumference about 82 in.

    286

    Observations with the xanthometer have not hitherto been numerous, but it appears that the purest blue (o--I on Forel's scale) is found in the Sargasso Sea, in the North Atlantic and in similarly situated tropical or subtropical regions in the Indian and Pacific Oceans.

    287

    Of course, for many purposes, mean conditions may be adopted and mean scale-values be found which are applicable with considerable pre cision to small angles or to comparatively crude observations of large distances; but the highest refinement is lost unless means are provided for determining the scale-value for each observer at each epoch of observation.

    288

    Of his numerous publications, For the use of the drum in the 16th century, see Sir John Smyth, Instructions and Observations for all Chieftaines, Captaines, &c. (London, 1 595), pp. 158-159.

    289

    On one occasion twelve observations, extending over half an hour, were made on a single arc, the calculated heights varying in a fairly regular fashion from 1 6 to 12.9 km.

    290

    On the 17th of December, however, Bradley observed that the star was moving southwards, a motion further shown by observations on the loth.

    291

    On the 6th of November in that year he plainly saw the living parasites under the microscope in the blood of a malarial patient, and he shortly afterwards communicated his observations to the Paris Academie de Medecine.

    292

    On the different days of the year each hour was determined by a fixed star culminating or nearly culminating in it, and the position of these stars at the time is given in the tables as in the centre, on the left eye, on the right shoulder, &c. According to the texts, in founding or rebuilding temples the north axis was determined by the same apparatus, and we may condude that it was the usual one for astronomical observations.

    293

    On the one hand he worked out the general theory of the magnetic circuit in the dynamo (in conjunction with his brother Edward), and the theory of alternating currents, and conducted a long series of observations on the phenomena attending magnetization in iron, nickel and the curious alloys of the two which can exist both in a magnetic and non-magnetic state at the same temperature.

    294

    On the other hand he unwisely rejected the results of the observations for latitude made by Pytheas in 326 B.C. at his native town, Massilia, and during a subsequent voyage to northern Europe.

    295

    On the other hand the experiences and observations of Felix Fabri, a Dominican monk who came to Palestine about A.D.

    296

    On the other hand, at Altjoch, an Alpine station, from nine days' observations in July 1903 they obtained a mean of 137, the maximum being 224, and the minimum 92.

    297

    On the other hand, the same observations go to show that the disease is met with oftener on the more recent formations than the older, and this fact, so far as concerns the physical characters of the soil, is identical with the questions of permeability to air and water.

    298

    On the side of the philosophy of science his observations are usually commonplace or superficial.

    299

    One member of the Cyprinidae is at present known to be viviparous, but no observations have as yet been made on its habits.

    300

    One of the chief observations recorded in it is that the atmosphere is composed of two gases - one which supports combustion and the other which prevents it.

    301

    One of the most important applications of the heliostat is as an adjunct to the newer forms of ' horizontal telescopes (q.v.) and in conjunction with spectroscopic telescopes in observations of eclipses.

    302

    One view of the origin of the latter (largely based upon observations upon the development of Polygordius) sees in the blood system a persistent blastocoel.

    303

    Only a few general observations can be made here.

    304

    Other observations concerning the manners and customs of the inhabitants.

    305

    Other observations made by Frankland at the time formed the starting-point of a series of experiments which yielded far-reaching results.

    306

    Other sources of uncertainty are, that the rate of loss of heat generally depends to some extent on the rate of fall of temperature, and that it is difficult to take accurate observations do a rapidly falling thermometer.

    307

    Owing to the difficulty of measuring the gradient, the order of divergence of individual observations averaged 2 or 3%, but occasionally reached 5 or io %.

    308

    Owing to the famine and the disturbed state of the country, which demanded his attention as a large landowner and lieutenant of King's County (from 1831), the instrument remained unused for nearly three years, but since 1848 it has been in constant use, chiefly for observations of nebulae, for which it was particularly suited on account of its immense optical power, nominally 6000.

    309

    Owing to the physical changes produced in the material exposed prolonged observations of temperature are impossible.

    310

    Pouqueville, who spent no less than ten years as French General Consul at Iannina, had special facilities for obtaining firsthand information and although his observations and deductions seemed at times somewhat suspect to the British they were later recognized as being truest to the realities of the epoch.

    311

    Primary, secondary and spurious bows were formed, and their radii measured; a comparison of these observations exhibited agreement with Airy's analytical values.

    312

    Pytheas certainly had one merit which distinguished him from almost all his contemporaries - he was a good astronomer, and was one of the first who made observations for the determination of latitudes, among others that of his native place Massilia, which he fixed with remarkable accuracy; his result, which was within a few miles of the truth, was adopted by Ptolemy, and became the basis of the Ptolemaic map of the western Mediterranean.

    313

    Ray himself published an account of his foreign travel in 1673, entitled Observations topographical, moral, and physiological, made on a Journey through part of the Low Countries, Germany, Italy, and France.

    314

    Regnault confirmed Neumann's observations, and showed that the molecular heat depended on the number of atoms present, equiatomic compounds having the same molecular heat.

    315

    Regnault in the years 1862 to 1866 on the velocity of sound in open air, in air in pipes and in various other gases in pipes, he sought to eliminate personal equaticn by dispensing with the human element in the observations, using electric receivers as observers.

    316

    Regular observations were made of both elements.

    317

    Richard, L'Oceanographie (Paris, 1907); List of Oceanic Depths and Serial Temperature Observations, received at the Admiralty in the year 1888 (et seq.) from H.M.

    318

    Richard, was followed in 1820 by an original Monographia Rosarum, with descriptions of new species, and drawings executed by himself, and in 1821 by Monographia Digitalium, and by "Observations on Pomaceae," contributed to the Linnean Society.

    319

    Rothe and Alexander Smith's interesting observations on sulphur, results have been obtained which tend to prove that the melting-point, as well as the appearance of two layers in the liquid state, correspond to unstable conditions.

    320

    Schott gives the following as the result of measurements of transparency by means of a white disk at 23 stations in the open ocean, where quantitative observations of the plankton under i square metre of surface were made at the same time.

    321

    Scientific exploration does not begin before Edward Robinson, an American clergyman, who, after devoting many years to study to fit himself for the work, made a series of journeys through the country, and under the title of Biblical Researches in Palestine (1841-1856) published his itineraries and observations.

    322

    See Rhode, Res Lemnicae; Conze, Reise auf den Inseln des Thrakischen Meeres (from which the above-mentioned facts about the present state of the island are taken); also Hunt in Walpole's Travels; Belon du Mans, Observations de plusieurs singularitez, &c.; Finlay, Greece under the Romans; von Hammer, Gesch.

    323

    Serious doubt was first cast upon its accuracy by the observations of Nyren with the same instrument during the years 1880-1882, but on a much larger number of stars.

    324

    Silurian and Devonian fossils have been reported at one or two localities, but for the present the observations are open to doubt.

    325

    Similar observations were made by Laurie (17) in Lankester's laboratory (1890) with regard to the early condition of the coxal gland of Scorpio, and by Bertkau (41) as to that of the spider Atypus.

    326

    Since 1870 thermometers on this principle have been in use for regular observations at German coast and light-ship stations.

    327

    Since the transit circle is preferable to the equatorial for such observations wherein great accuracy is required, the declination and hour circles of an equatorial are employed, not for the determination of the right ascensions and declinations of celestial objects, but for directing the telescope with ease and certainty to any object situated in an approximately known position, and which may or may not be visible to the naked eye, or to define approximately the position of an unknown object.

    328

    Solutions were not distinguished from definite chemical compounds till John Dalton discovered the laws of definite and multiple proportions, but many earlier observations on the solubility of solids in water and the density of the resulting solutions had been made.

    329

    Some observations, however, of Guy Marshall on the inedibility of certain birds suggest that the resemblance between cuckoos a'nd hawks on the one hand and cuckoos and drongos on the other may be susceptible of another explanation in full agreement with the theory of mimicry as propounded by Bates.

    330

    Some sensible observations by the editor were added to the original biography.

    331

    Sosigenes Could Scarcely Fail To Know That This Year Was Too Long; For It Had Been Shown Long Before, By The Observations Of Hipparchus, That The Excess Of 3654 Days Above A True Solar Year Would Amount To A Day In 300 Years.

    332

    Special Observations Were Made To Determine The Corrections For The Heat Supplied By Stirring, And That Lost By Radiation, Each Of Which Amounted To About To% Of The Heatsupply.

    333

    Starting from these men arose a school of physicians who endeavoured to give to the study of symptoms the same precision as belonged to anatomical observations, and by the combination of both methods made a new era in clinical medicine.

    334

    Still, you must have some personal observations... thoughts... feelings?

    335

    Struve's name is best known by his observations of double stars, which he carried on for many years.

    336

    Subsequent volumes of the same series contained his observations of the transits of Venus (1761 and 1769), on the tides at St Helena (1762), and on various astronomical phenomena at St Helena (1764) and at Barbados (1764).

    337

    Such observations, however, were but rarely available at the time.

    338

    Suppose now, for the moment, that the readings of the levels k and l are identical in both observations, we have then, in the difference between the micrometer readings north and south, a measure of the difference of the two zenith distances expressed in terms of the micrometer screw; and, if the "` value of one revolution of the micrometer screw" is known in seconds of arc we have for the resulting latitude FIG.

    339

    Swammerdam's Biblia naturae, issued in 1737, fifty years after its author's death, and containing observations on the structure and lifehistory of a series of insect types.

    340

    Taylor Jones showed in 1897 that only a small proportion of the contraction exhibited by a nickel wire when magnetized could be accounted for on Kirchhoff's theory from the observed effects of pulling stress upon magnetization; and in a more extended series of observations Nagaoka and Honda found wide quantitative divergences between the results of experiment and calculation, though in nearly all cases there was agreement as to quality.

    341

    Thackeray, and proper motions derived by comparison with modern Greenwich observations.

    342

    That in man the excitable foci of the motor field are islanded in excitable surface similarly and even more extensively, was a natural inference, but it had its chief basis in the observations on the orang, now known to be erroneous.

    343

    That some suras were of considerable length from the first is seen, for example, from xii., which contains a short introduction, then the history of Joseph, and then a few concluding observations, and is therefore perfectly homogeneous.

    344

    The above observations relate to transmitted light, but Fraunhofer extended his inquiry to the light reflected.

    345

    The accounts of the observations given in these papers, however, were fragmentary; but in 1879-80 a complete account of them was published by the present earl ("Observations of Nebulae and Clusters of Stars made with the 6-foot and 3-foot Reflectors at Birr Castle from 1848 to 1878") in the Scient.

    346

    The Advantage Of This Method Is That All The Conditions Are Steady, So That The Observations Can Be Pushed To The Limit Of Accuracy And Fig.

    347

    The amount of sediment carried down is very large, though no accurate observations have been made.

    348

    The book, as it stands, is a collection of the discourses, observations and aphorisms of a sage called Koheleth, a term the precise meaning of which is not certain.

    349

    The building was finished in 1832, and the instruments were ready for work in 1835, from which date the observations were published in 4to volumes (Annales de l'Observatoire Royal de Bruxelles), but Quetelet chiefly devoted himself to meteorology and statistics.

    350

    The chief uncertainty in declination observations, at any rate at a fixed observatory, lies in the variable torsion of the silk suspension, as it is found that, although the fibre may be entirely freed from torsion before beginning the declination observations, yet at the conclusion of these observations a considerable amount of torsion may have appeared.

    351

    The classical observations of Reaumur Memoires pour servir a l'histoire des insectes, vols.

    352

    The combined result from both these methods is 8.857", while the combination of all the contact observations made by all the parties gave the much smaller result, 8.794".

    353

    The comparison of observations in various climates and peoples has had some weight; while in the better knowledge of their causes their treatment has found permanent advantage.

    354

    The conjugation of similar gametes, arising from distinct plurilocular sporangia, was observed by Berthold in Ectocarpus siliculosus and Scytosiphon lomentarius in 1880; and these observations have been recently confirmed in the case of the former species by Sauvageau, and in the case of the latter by Kuckuck.

    355

    The constancy of composition shown by repeated analyses of atmospheric air led to the view that it was a chemical compound of nitrogen and oxygen; but there was no experimental confirmation of this idea, and all observations tended to the view that it is simply a mechanical mixture.

    356

    The Copernican theory of the solar system - that the earth revolved annually about the sun - had received confirmation by the observations of Galileo and Tycho Brahe, and the mathematical investigations of Kepler and Newton.

    357

    The curve, and the observations it represents, are drawn in fig.

    358

    The difficulties arise in connexion with the determination of the quantities of ice melted or steam condensed, and in measuring the latent heat of fusion or vaporization in terms of other units for the comparison of observations.

    359

    The diffusivity can be deduced from observations at different depths x' and x", by observing the ratio of the amplitudes, which is (x '- x ") for a simple-harmonic wave.

    360

    The drawback of greater distance was, however, in Gill's opinion, more than compensated by the accuracy with which the observations could be made.

    361

    The earliest Arabian traveller whose observations have come down to us is the merchant Sulaiman, who embarked in the Persian Gulf and made several voyages to India and China, in the middle of the 9th century.

    362

    The establishment of a system of magnetic observatories in various parts of British territory all over the globe was accomplished mainly on his representations; and a great part of his life was devoted to their direction, and to the reduction and discussion of the observations.

    363

    The existence of the latter, which extends to the African continent, was announced by Sir Wyville Thomson in 1876 as a result of his discussion of the deep-sea temperature observations of the " Challenger " expedition, though the fact was not confirmed by soundings until many years later.

    364

    The external form of the embryo goes through the same changes as in other Gastropods, and is not, as was held previously to Lankester's observations, exceptional.

    365

    The external heat-loss was eliminated by comparing observations taken at the same mean temperatures during heating and during cooling, assuming that the rate of loss of heat f(S) would be the same in the two cases.

    366

    The eye-pieces or oculars through which, in case of visual observations, the primary images formed by the objective are viewed, are of quite secondary importance as regards definition in the central portion of the field of view.

    367

    The fact that sea-water does evaporate more slowly than fresh water has been proved by the observations of Mazelle at Triest and of Okado in Azino (Japan).

    368

    The failure of the method based on transits of Venus led to an international effort carried out on the initiative of Sir David Gill to measure the parallax by observations on those minor planets which approach nearest the earth.

    369

    The figures being based on only one season's observations are somewhat irregular.

    370

    The first of these works is the Compendium medicinae, also called Laurea or Rosa anglicana, of Gilbert (Gilbertus Anglicus, about 1290), said to contain good observations on leprosy.

    371

    The first step in this direction was effected by the co-ordination of Gay Lussac's observations on the combining volumes of gases.

    372

    The first to take up the camera obscura after Porta was Kepler, who used it in the old way for solar observations in 1600, and in his Ad Vitellionem Paralipomena (1604) discusses the early problems of the passages of light through small apertures, and the rationale of the simple dark chamber.

    373

    The French observations were published in 1792 (Expose des operations faites en France in 1787 pour la jonction des observatoires de Paris et de Greenwich).

    374

    The general level of the Nafud was found by Huber's observations to be about 3000 ft.

    375

    The gradient near the entrance to the calorimeter was deduced from observations with five thermometers at suitable intervals along the bar.

    376

    The Gundlingiana of the latter person, published at Halle (1715-1732), and written partly in Latin and partly in German by the editor, contained a miscellaneous collection of juridical, historical and theological observations and dissertations.

    377

    The Hessian star catalogue was published in Lucius Barettus's Historia coelestis (Augsburg, 1668), and a number of other observations are to be found in Coeli et siderum in eo errantium observationes Hassiacae (Leiden, 1618), edited by Willebrord Snell.

    378

    The highest pressures recorded for cane-sugar are nearly three times as great as those given by van't Hoff's formula for the gas-pressure, but agree very well with the vapour-pressure theory, as modified by Callendar, provided that we substitute for V in Arrhenius's formula the actual specific volume of the solvent in the solution, and if we also assume that each molecule of sugar in solution combines with 5 molecules of water, as required by the observations on the depression of the freezing-point and the rise of the boiling-point.

    379

    The indicated horse-power developed by a cylinder may always be ascertained from an indicator diagram and observations of the speed.

    380

    The inspector, after making his investigation, is required to make a report to the Board of Trade as to the causes of the accident and the circumstances attending the same, with any observations on the subject which he deems right, and the Board " shall cause every such report to be made public in such manner as they think expedient."

    381

    The instrument is, of course, supported on a gimballed table, while the ship during the observations is kept on a fixed course.

    382

    The instrument was set up in November 1725, and observations on y Draconis were made on the 3rd, 5th, 11th, and 12th of December.

    383

    The interesting observations of Morland, already quoted, seem to have been neglected, and no one attempted to follow in the path which he had pointed out.

    384

    The island is not permanently inhabited, but has been frequently visited by explorers, sealers and whalers; and an Austrian station for scientific observations was maintained here for a year in 1882-1883.

    385

    The magnetic observations, though imperfect, led him to the conclusion that the magnetic effect at all attainable elevations above the earth's surface remains constant; and on analysing the samples of air he could find no difference of composition at different heights.

    386

    The mean height calculated at Arctic stations, where careful observations have been made, in this or analogous ways, has varied from 58 km.

    387

    The mean temperature gradient is found by plotting the curves for each day from the daily observations.

    388

    The measurement of the declination involves two separate observations, namely, the determination of (a) the magnetic meridian and (b) the geographical meridian, the angle between the two being the declination.

    389

    The method is interesting, but the manipulations and observations involved are more troublesome than with the ordinary type of calorimeter, and it may be doubted whether any advantage is gained in accuracy.

    390

    The method was proposed by Legendre only as a convenient process for treating observations, without reference to the theory of probability.

    391

    The modern practice is to take rapid observations rather than to keep the periscope above the water all the time.

    392

    The most careful observations are those by Fiirbringer.

    393

    The most valuable intellectual possession was a large mass of recorded observations in individual cases and epidemics of disease.

    394

    The motions of the earth as a planet must be taken into account, as they render possible the determination of position and direction by observations of the heavenly bodies.

    395

    The observations made on the " Challenger " and " Gazelle," though enabling some perfectly sound general conclusions to be drawn, require to be supplemented.

    396

    The observations of Aime in 1845 and of Semmola in the Gulf of Naples in 1881 show that the surface water in winter cools until the whole mass of water from the surface to the bottom, in 1600 fathoms or more, assumes the same temperature.

    397

    The observations of Chardin, who flourished between 1643 and 1713, cannot be said to receive support from the testimony of some earlier authorities.

    398

    The observations of Moller, &c., on the germination cannot be assumed to negative the sexual hypothesis for the sexual cells of Ulothrix and Ectocarpus, for example From Strasburger's Lehrbuch der Botanik, by permission of Gustav Fischer.

    399

    The observations of Schwendener, however, received ample support from Bornet's (1873) examination of 60 genera.

    400

    The Observations of Sir Richard Hawkins in his Voyage into the South Sea, published in 1622, are very valuable.

    401

    The observations of Strachey, Godwin-Austen and of Griesbach and other members of the Geological Survey of India only extend to the southern edge or rim of the great plateau, where vast alluvial deposits in horizontal strata have been furrowed into deep ravines, while Russian explorers have but superficially examined the mountain regions of the north and north-east, and the British mission to Lhasa, in 1904 afforded observations merely along the trade-route to that city.

    402

    The observations were continued, and the star was seen to continue its southerly course until March, when it took up a position some 20" more southerly than its December position.

    403

    The observations were usually confined to a few hours of the day, very commonly between II A.M.

    404

    The party therefore camped on the drifting floe, keeping up scientific observations and maintaining their health and spirits though in continual danger from the floes ridging up or cracking asunder.

    405

    The Phaenomena of Aratus is a poetical account of the astronomical observations of Eudoxus.

    406

    The photographs led to no more definite result than the observations of contacts, except perhaps those taken by the Americans, who had adopted a more complete system than the Europeans; but even these were by no means satisfactory.

    407

    The pilots were all Indians, and they used the forestaff and quadrant for their observations.

    408

    The position of the middle of the bright band representative of a mathematical line can be fixed with a spider-line micrometer within a small fraction of the width of the band, just as the accuracy of astronomical observations far transcends the separating power of the instrument.

    409

    The present practice being the dominant one from the time of Ptolemy until the present, it was felt that the confusion in the combination of past and present astronomical observations, and the doubts and difficulties in using the astronomical ephemerides, formed a decisive argument against any change.

    410

    The principal fruit of the observations was a catalogue of about a thousand stars, the places of which were determined by the methods usually employed in the 16th century, connecting a fundamental star by means of Venus with the sun, and thus finding its longitude and latitude, while other stars could at any time be referred to the fundamental star.

    411

    The principle gives an instantaneous solution of the question of the ultimate optical efficienc y in the method of " mirror-reading," as commonly practised in various physical observations.

    412

    The problem is greatly complicated by the fact that the equator and equinox, to which the observed positions of the stars must be referred, are not stationary in space, and in fact the movements of these planes of reference can only be determined by a discussion of the observations of stars.

    413

    The purity of the compounds thus obtained is checked by spectroscopic observations.

    414

    The qualification " almost " is necessary because so complex a system of actions comes into play, and accurate observations have extended through so short a period, that the proof cannot be regarded as absolute.

    415

    The rainfall on the summit is heavy, 72.14 inches a year being the average of twelve years' observations.

    416

    The rates of motion are so slow that many centuries' observations are needed to determine the orbit.

    417

    The real velocities derived from good observations are rarely, if ever, under 7 or 8 m.

    418

    The recent observations and exceedingly ingenious experiments of Falck have shown that the sporophores of the Basidiomycetesespecially the large sporophores of such forms as Boletus, Polyporus- contain quantities of reserve combustible material which are burnt up by the active metabolism occurring when the fruit-body is ripe.

    419

    The records of Delisle's observations at St Petersburg are preserved in manuscript at the Pulkowa observatory.

    420

    The result of his observations was published from time to time in the Journal des Mines and other scientific journals.

    421

    The result of this would be seen in the motions of the planets around the sun; but the most refined observations show no such effect.

    422

    The results of his observations during his journey through England and Scotland appeared in a tract De l'Angleterre et des Anglais; and his conversations with distinguished men in those countries contributed to greater correctness in the exposition of principles in the third edition of the Traite, which appeared in 1817.

    423

    The results of Secchi's observations are contained in a great number of papers and memoirs.

    424

    The results of these observations are entered in a compass journal for future reference when fog or darkness prevails.

    425

    The Scandinavian data, from the wealth of observations, are probably the most representative, and even in the most northern district of Scandinavia the smallness of the excess of the frequencies in December and January over those in March and October suggests that some influence tending to create maxima at the equinoxes has largely counterbalanced the influence of sunlight and twilight in reducing the frequency at these seasons.

    426

    The scheme of observations was organized on an extended scale.

    427

    The solution came abOut by arranging the elements in the order of their atomic weights, tempering the arrangement with the results deduced from the theory of valencies and experimental observations.

    428

    The stars had been numbered and named at an early date, and we possess tables of lunar longitudes and observations of the phases of Venus.

    429

    The subject was next taken up by Hans Landolt, who, from an immense number of observations, supported in a general way the formula of Gladstone and Dale.

    430

    The Swiss physician, Theophile Bonet (1620-1689) had published his Sepulcretum in 1679; and observations of post mortem appearances had been made by Montanus, P. Tulp, Raymond Vieussens, A.M.

    431

    The value of c is determined by the throttling experiments, so that all the coefficients in the formula with the exception of A are determined independently of any observations of the saturationpressure itself.

    432

    The values of the saturation-pressure given in the last column are calculated by formula (25), which agrees with Regnault's observations better than his own empirical formulae.

    433

    The velocity 109.09 was much the largest observed, the next being 52.38; both were from observations lasting under half a minute.

    434

    The views of neither of these systematizers pleased Temminck, who in 1817 replied rather sharply to Vieillot in some Observations sur la classification methodique des oiseaux, a pamphlet published at Amsterdam, and prefixed to the second edition m i nd.

    435

    The work of translating the law of gravitation into the form of astronomical tables, and the comparison of these with observations, has been in progress ever since.

    436

    Their observations on the solid elements led to a remarkable generalization, now known as Dulong and Petit's law.

    437

    Their reproduction and development were first described by a Dutch naturalist from observations made on the shores of the Zuider Zee.

    438

    There are also indications that the extensive texts dealing with divination through the liver of sacrificial animals, which represents a more popular origin than divination through the observations of the heavens, based as it is on the primitive view which regarded the liver as the seat of life and of the soul, were brought into connexion with astral divination.

    439

    There are deer (at least five species), boars, bears, antelopes, beavers, otters, badgers, tiger-cats, marten, an inferior sable, striped squirrels, &c. Among birds there are black eagles, peregrines (largely used in hawking), and, specially protected by law, turkey bustards, three varieties of pheasants, swans, geese, common and spectacled teal, mallards, mandarin ducks white and pink ibis, cranes, storks, egrets, herons, curlews, pigeons, doves, nightjars, common and blue magpies, rooks, crows, orioles, halcyon and blue kingfishers, jays, nut-hatches, redstarts, snipe, grey shrikes, hawks, kites, &c. But, pending further observations, it is not possible to say which of the smaller birds actually breed in Korea and which only make it a halting-place in their annual migrations.

    440

    There are some observations on the transparency of sea-water of an entirely different character.

    441

    There has also been a certain amount of geographical sketching combined with trigonometrical observations; and there are the route surveys of native explorers.

    442

    There is a set of Annual Bills from 1658 (with the exception of the years 1756 to 1764) in the library of the British Museum.3 These bills were not analysed and general results obtained from them until 1662, when Captain John Graunt first published his valuable Natural and Political Observations upon the Bills of 1 In a valuable paper on " The Population of Old London" in Blackwood's Magazine for April 1891.

    443

    There is also difficulty in ensuring that the observations shall be simultaneous, an important matter especially when the apparent velocity is considerable.

    444

    There were also two intermediate stations at which observations were made.

    445

    These are easily calculated on the assumption first that the observations were correctly made, secondly that the calendrical dates are in the year of 365 days beginning on.

    446

    These averages are based on the observations of seven years only.

    447

    These four nations sent out well-equipped expeditions to various quarters of the globe, both in 1874 and 1882, to make the required observations; but when the results were discussed they were found to be extremely unsatisfactory.

    448

    These include the mutual distances of some of the stars in the Pleiades, a few observations of the apparent diameter of the sun, others of the distance of the moon from neighbouring stars, and a great number of measurements of the diameter of the moon.

    449

    These last observations are, however, regarded as uncertain.

    450

    These materials generally include reconnaissance survey of small districts, route surveys and astronomical observations supplied by travellers, and information obtained from native sources.

    451

    These men were specially Service trained at Dehra Dun in the work of surveying, and entered Tibet with a strong wooden box with a specially concealed secret drawer for holding observing instruments, .a prayer wheel with rolls of blank paper instead of prayers in the barrel on which observations might be noted, and lamaic rosaries by the beads of which each hundred paces might be counted.

    452

    These observations admit of ready explanation in the following manner.

    453

    These observations confirmed by experimental demonstration the hypothetical conclusions of Bell.

    454

    These observations give values for S ranging from 0.30 to o 46, with a mean value 0.3778.

    455

    These observations have an important bearing upon the molecular theory of magnetism, which will be referred to later.

    456

    These observations have been verified and extended by Knott, whose researches have brought to light a large number of additional facts, all of which are in perfect harmony with Maxwell's explanation of the twist.

    457

    These observations have been verified in the rabbit, mouse, fowl, guinea-pig and cat by Davidsohn, occasionally in the dog by Lubarsch; and confirmatory observations have also been made by Czerny and Maximoff.

    458

    These observations may be summarized by saying that the benzene nucleus is more negative in character than the aliphatic residues.

    459

    These pairs of observations have shown a parallax from which the elevation of the objects above the earth, the lengths and directions of their courses, &c. could be computed.

    460

    They are employed for taking observations of the density of sea-water.

    461

    This deduction harmonized the observations of Andrews and of Hess previously alluded to, and also accounted satisfactorily for the Law of Thermoneutrality.

    462

    This general view is set forth in a number of particular observations.

    463

    This observatory, the foundations of which were fixed in the snow that appears to cover the summit to a depth of ten metres, was built in September 1893, and Janssen, in spite of his sixty-nine years, made the ascent and spent four days taking observations.

    464

    This theory Gibbon completely exploded in his Critical Observations (1770) - no very difficult task, indeed, but achieved in a style, and with a profusion of learning, which called forth the warmest commendations both at home and abroad.

    465

    This value, although considerably in excess of that previously found by different methods, was held by Airy, from the care and completeness with which the observations were carried out and discussed, to be "entitled to compete with the others on, at least, equal terms."

    466

    This was followed by a zone-catalogue of 73,160 stars (1884), and a general catalogue (1885) compiled from meridian observations of 32,448 stars.

    467

    This was nothing less than the complete revision of the planetary theories, followed by a laborious comparison of results with the most authentic observations, and the construction of tables representing the movements thus corrected.

    468

    This will turbocharge science, which will no longer rely exclusively on slow observations in real time.

    469

    Thompson, From the Cotton Field to the Cotton Mill, a Study of the Industrial Transition in North Carolina (New York, 1906), contains some interesting observations on the changes in social conditions resulting from the growth of the cotton-manufacturing industry.

    470

    Thomson (afterwards Lord Kelvin) in 1847, as the result of a mathematical investigation undertaken to explain Faraday's experimental observations.

    471

    Thomson, who, from the results of Bidwell's observations on the magnetic deformation of cobalt, was led to expect that that metal would exhibit a reversal opposite in character to the effect observed in iron.

    472

    Thus the heaviest measured rainfall east of the Mississippi is on the southern Appalachians; while in the west, where observations are as yet few at high level stations, the occurrence of forests and pastures on the higher slopes of mountains which rise from desert plains clearly testifies to the same rule.

    473

    Thus the recapitulation law, which had been built up independently from the observations and speculations on vertebrates by Lorenz Ofen (1779-1851), Johann Friedrich Meckel (1781-1833), St Hilaire, Karl Ernst von Baer (1;92-1876) and others, and had been applied (1842-1843) by Karl Vogt (1817-1895) and Agassiz, in their respective fields of observation, to comparison of individual stages with the adults of the same group in preceding geological periods, furnished the key to the determination of the ancestry of the invertebrates generally.

    474

    Thus there arose a chaos of controversy, illuminated by definite measurements and observations.

    475

    Thus Whewell mistook Kepler's inference that Mars moves in an ellipse for an induction, though it required the combination of Tycho's and Kepler's observations, as a minor, with the laws of conic sections discovered by the Greeks, as a major, premise.

    476

    To determine proper motions it is necessary to have observations separated by as long a period of time as possible.

    477

    Trans., 1830); and in 1830 he erected in the hall of the Royal Society a waterbarometer, with which he carried out a large number of observations (Phil.

    478

    Transits of Venus and observations of Deterrnina- various kinds on Mars are all to be included in this tion.

    479

    Two groups of observations were recorded, one giving the induction in the inner coil and the other that in the outer coil.

    480

    Two sets of observations are taken, one when the blocks are fixed at the ends of the bars, and another when they are nearer together, the clear length of the bars.

    481

    Under the influence of the touchstone of strict inquiry set on foot by the Royal Society, the marvels of witchcraft, sympathetic powders and other relics of medieval superstition disappeared like a mist before the sun, whilst accurate observations and demonstrations of a host of new wonders accumulated, amongst which were numerous contributions to the anatomy of animals, and none perhaps more noteworthy than the observations, made by the aid of microscopes constructed by himself, of Leeuwenhoek, the Dutch naturalist (1683), some of whose instruments were presented by him to the society.

    482

    Unfortunately no observations of evaporation from the surface of the open sea have been made and very few comparisons of the evaporation of salt and fresh water are on record.

    483

    Valuable observations were made in oceanography during the expeditions of Captain James Cook and the polar explorers, especially those of Sir John Ross in the north and Sir James Ross in the south, but the voyage of H.M.S.

    484

    Vauquelin in 1797, and Klaproth's investigation of tellurium in 1798, the next important series of observations was concerned with platinum and the allied metals.

    485

    Verdet's own observations, conducted with great care, fully confirm this view, and exhibit a complete agreement with theory.

    486

    Very elaborate observations have been made during several Arctic expeditions of the azimuths of the summits of auroral arcs.

    487

    Very special precautions are required to eliminate instrumental error before we can compare observations, say, of a star on the meridian in winter at 6 p.m.

    488

    Villele, who before the promulgation of the charter had written some Observations sur le projet de constitution opposing it, as too democratic in character, naturally took his place on the extreme right with the ultra-royalists.

    489

    Wallace notes the resemblance which he traced between the Malays and the Mongolians, and others have recorded similar observations as to the physical appearance of the two races.

    490

    We are still ignorant of the depth to.which the annual temperature wave penetrates in the open ocean, but observations in the Mediterranean enable us to form some opinion on the matter.

    491

    We may, however, notice Heinrich Rose i and Friedrich WShler, 2 who, having worked up the results of their teacher Berzelius, and combined them with their own valuable observations, exerted great influence on the progress of analytical chemistry by publishing works which contained admirable accounts of the then known methods of analysis.

    492

    Westermarck has shown from his observations in Morocco that the blood of the victim was considered to visit a curse upon the object to whom the sacrifice is offered and thereby the latter is made amenable to the sacrificer.

    493

    When A, B and C are objects of sense, their relative positions are matters, not of inference, but of observation; when they are not, there is an inference, but a syllogistic inference with a major premise, induced from previous observations, " whenever of three things the first is to the right of the second, and the second to the right of the third, the first is to the right of the third."

    494

    When her brother accepted the office of astronomer to George III., she became his constant assistant in his observations, and also executed the laborious calculations which were connected with them.

    495

    Where accurate differential observations or photographs involving other than instantaneous exposures have to be made, the additional condition is required that the optical axis of the telescope shall accurately and automatically follow the object under observation in spite of the apparent diurnal motion of the heavens, or in some cases even of the apparent motion of the object relative to neighbouring fixed stars.

    496

    Whether these observations were systematic or individual, and how they were recorded, are points of which we are quite ignorant, as the theory that the votive tablets in the temples supplied such materials must be abandoned.

    497

    While furnishing - almost unconsciously, however - additional evidence for overthrowing that classification, there is, nevertheless, no attempt made to construct a better one; and the elaborate tables of dimensions, both absolute and proportional, suggestive as is the whole tendency of the author's observations, seem not to lead to any very practical result, though the systematist's need to look beneath the integument, even in parts that are so comparatively little hidden as birds' feet, is once more made beyond all question apparent.

    498

    While in Greece he made observations which showed that in ancient architecture the use of polychrome was frequent.

    499

    While the sailors' logs supply the greater part of the scientific evidence available for the study of the surface phenomena of the ocean, they have been supplemented by the records of numerous scientific expeditions and latterly by publications embodying systematic observations on a permanent basis.

    500

    With the object of reaching fainter stars, Professor Pickering constructed another instrument of larger dimensions, and with this more than a million observations have been made.