5MI4 Biographical Memoir of M. Hauy. 



the same gelatin in their membranes, the same phosphate of lime 

 in their bones. Like calcareous spar and arragonite, 4;hey differ 

 only in the form which these substances have assumed at the mo- 

 ment when they constituted individuals. 



I beg to be understood as by no means intending to assert, 

 that the chemical analysis of minerals should be neglected, nor 

 was it M. Haiiy's opinion that it should. Their analysis is as 

 necessary for acquiring a knowledge of them as the determination 

 of their form, and is much more important with relation to their 

 uses. What M. Haiiy maintained was, that it is generally in- 

 adequate to the determination of their species, because it has no 

 sure means of distinguishing the accidental from the essential sub- 

 stances ; because it is not in a condition, with respect to certain 

 classes of stones, to affirm that it knows their elements, and be- 

 cause it every day discovers elements which were previously con- 

 cealed from it *. . 



The late Werner, whom Europe has long considered as a rival, 

 and even as an adversary, of M. Haiiy, differed in reality from 

 him, only in not going so far in the search of principles. The 

 hardness, the fracture, the texture to which he attached himself 

 by preference, are in reality nothing but consequences of the 

 form of the molecules and of their arrangement, and the happy 

 use which that mineralogist made of them for discovering and 

 determining so many mineral species, might already have made 

 all that the source of these, since mere derivations were so pro- 

 lific. But this source it was reserved for M. Haiiy alone, not only 

 to discover, but also to measure its force and plenitude ; and it 

 was for him only that it was possible to carry or bring back to 

 their just value many results, which, in Werner"'s hands, re- 

 mained in some measure only half truths. 



There is scarcely, at the present day, a crystaUizable mineral 

 known of which M. Haiiy has not determined the nucleus and 

 molecules, with the measure of their angles and the proportion 

 of their sides ; and of which he has not referred to these first ele- 

 ments all the secondary forms, by determining for each the va- 

 rious decrements which produce it, and fixing their angles and 



• Tableau comparatif des resultats de la cristallographio, et de I'analyse chi- 

 mique relativement a la classification des min^raux. 1 Vol. 8vo, Paris, 1809. 



