He established the existence of two new elements, samarium and gadolinium, since investigated more especially by Cleve, to whom most of our knowledge on this subject is due.
In 1879, however, Lecoq de Boisbaudran showed that Mosander's "didymium," contained samarium; while the residual "didymium" after removal of samarium, was split by Auer v.
Meyer thinks that the susceptibilities of the metals praseodymium, neodymium, ytterbium, samarium, gadolinium, and erbium, when obtained in a pure form, will be found to equal or even exceed those of the well-known ferromagnetic metals.