216 HISTORY OF MINERALOGY. 



remain constantly the same. But when the whole 

 shape varied so much, the angles also seemed to 

 vary. Thus Conrad Gessner, a very learned natu- 

 ralist, who, in 1564, published at Zurich his work, 

 De rerum Fossilium, Lapidum et Gemmarum 

 maxime, Figuris, says 2 , " One crystal differs from 

 another in its angles, andconsequently in its figure." 

 And Csesalpinus, who, as we shall find, did so much 

 in establishing fixed characters in botany, was led 

 by some of his general views to disbelieve the fixity 

 of the form of crystals. In his work De Metallicis, 

 published at Nuremburg in 1602, he says 3 , "To 

 ascribe to inanimate bodies a definite form, does 

 not appear consentaneous to reason; for it is the 

 office of organization to produce a definite form ;" 

 an opinion very natural in one who had been 

 immersed in the study of the general analogies of 

 the forms of plants. But though this is excusable 

 in Csesalpinus, the rejection of this definiteness of 

 form a hundred and eighty years later, when its 

 existence had been proved, and its laws developed 

 by numerous observers, cannot be ascribed to any- 

 thing but strong prejudice ; yet this was the course 

 taken by no less a person than Buffon. " The form 

 of crystallization," says he 4 , "is not a constant cha- 

 racter, but is more equivocal and more variable 

 than any other of the characters by which minerals 

 are to be distinguished." And accordingly, he makes 

 no use of this most important feature in his history 

 2 p. 25. 3 p. 97. 4 Hist, des Mm. p. 343. 



