CRTSTALLISED GADOLINffE. 347 



In 1794, M. Gadolin analyfed it, and found that it con- 

 tained 38 per cent, of an unknown earth, whofe properties 

 approached to alumine in fome refpects, and to calcare- 

 ous earth in others ; but that it eflentially differed from both, 

 as well as from every other known earth. 



In 1797 M. Ekeberg repeated the analyfis of M. Gado- 

 lin, and obtained 47 ± per cent, of the new earth. This in- 

 creafe of quantity he attributed to the greater purity of the 

 fpecimens he fubmitted to experiment, and in confequence of 

 having confirmed the difcovery of Gadolin, he called the 

 ftone after him, and gave the name of Yttria to the earth. 



Analyses by Vauqueln and Klaproth have fince ap- 

 peared. The quantity of yttria obferved by the former 

 amounted only to 35 per cent, j but the latter ftates 59^ per 

 cent. 



The fmall portions of this mineral, which, from its rarity, 

 it is natural to conclude were at the difpofal of thefe celebrated 

 chemifts, may in fome meafure account for the diverfity of 

 their refults ; but it is likewife by no means impollible, that the 

 mineral itfelf may have varied in the proportions of its chemi- 

 cal ingredients. 



The difference which we find in the mineralogical defcrip- 

 tions of this foffil." hitherto only found in one fpot, is much 

 more difficult to account for. If the information I have other- 

 wife obtained be correct, of which I have not the flighted 

 doubt, we cannot help attributing a certain degree of carelefE- 

 nefs to fome of the authors, particularly the French writers, 

 who have fuch opportunities at command *, of inveftigating 

 every point relative to natural hiftory. The great veneration 



Vol. VI. P. # II. X x they 



* Lucas notes the Gadolinite as one of the minerals in the collection at -the 

 jfardin dc Pluntes, 



