MEMOIR OF HAUY. 383 



Rome Delisle, even Saussure himself, confounded under the name of 

 schorl a multitude of stones which had nothing in common hut a certain 

 fusibility joined to a form more or less prismatic; and under that of 

 zeolite a multitude of others, whose sole distinctive character was to 

 change, with acids, into a sort of jelly. The schorls especially formed 

 a most heterogeneous assortment; every mineral of which there existed 

 no clear idea being referred to it ; which led the illustrious Lagrange 

 to say, jestingly, that schorl was the nectary of the mineralogists, be- 

 cause the botanists were similarly accustomed to call by the name ol 

 nectary every part of the flower whose nature they were ignorant of. 



On subjecting to mechanical division the stone known as white schorl, 

 (schorl-blanc ,) Hauy was surprised at finding the nucleus and molecule 

 of feld-spar. A test supplied upon this indication, by the chemist 

 Darcet, manifested the identity of the schorl in all its physical and 

 chemical characters with the feld-spars. 



Thus encouraged, Hauy proceeded to examine other schorls. He 

 discovered that the black stone with which so many lavas are strewn, 

 and which had been called volcanic schorl, has for its nucleus an ob- 

 lique prism with rhombic base, and the pretended violet schorl of Dau- 

 pliine a nucleus whose prism is straight; both, therefore, were to be 

 separated from the family of schorls. Still later, he succeeded in dis- 

 tinguishing the electric schorl or tourmaline from the black schorl of 

 primitive formation , the nucleus of the first being a regular hexahedral 

 prism, that of the last simply tetrahedral. Thus, one after another, 

 under his continued researches, the pretended schorls were divorced 

 from the varieties with which they had been improperly associated, and 

 assigned by tixed characters to their proper groups. The same success 

 attended his method in distinguishing the stones confounded under the 

 name of zeolites. Chemistry and physics, prompted by these results 

 of crystallography, were everywhere enabled to find in minerals char- 

 acters or elements which had not before been detected. 



From this time Hauy might be said to have become the lawgiver of 

 mineralogy. By his researches on the schorls he had inaugurated a 

 new era in the science; and every subsequent year has witnessed some 

 unexpected discovery, due to the study of the crystalline structure of 

 minerals. 



Among the schorls, he finally distinguished fourteen species, six 

 among the zeolites, four among the garnets, five among the jacinths. 

 Not only were the chemists guided by these labors to the detection of 

 unsuspected differences in the composition of stones ; there were scarcely 

 less frequent occasions when liaiiy could predict that the differences 

 which they had assumed could not exist. Thus, Vauquelin, who had 

 before discovered glucine in the beryl, was led by the indications of crys- 

 tallography to find it also in the emerald. 



It was not always that Hauy recognized at first the indications fur-* 

 nished by his own researches; he might sometimes neglect to compare 

 their results. When Klaproth and Vauquelin, for instance, had dis- 

 covered that the apatite and the chrysolite of the jewelers were but 

 phosphate of lime, Hauy, on recurring to his papers, found that he 

 had himself long before determined the same struc I : and 



