LANTHANUM

(Lat.), n. n. Laan(lan)'thas-nusm(num). From Aav*0<ii'eix. to hide. Fr., lanthane. Ger., Lanthan. A metallic element discovered in 1839 by Mosander. It is a malleable, iron-gray substance, susceptible of a high polish, and of the sp. gr. of 6' 163. In compounds it acts as a trivalent radicle, replacing 3 atoms of hydrogen. Symbol, La; atomic weight, 139. [B, 3.] [s. 578]