CHEMICAL ANALYSIS OP SOME CALAMINES, gj 



but the differences which exift are owing, in feme meafure Elucidations of 

 at leaft, to iho admixture of carbonate of lime and carbonate "^^^"^'"^ t^^"''/* 

 of lead, in the calamine analyfed, and alfo to feme portion 

 of water, which is undoubtedly contained, in the ftate of 

 moifture, in fo porus and bibulous a body. 



It has alfo appeared, in the experiments on the Mendip 

 Hill calamine, that acids indicate a greater quantity of carbonic 

 acid than fire does, -^--q. If we make this dedu6tion for 

 diflTolved water, it reduces the quantity of carbonic acid in the 

 Bley berg calamine, to 0.1321. 



If we affume this quantity of carbonic acid as the datum to 

 calculate, on this fyftem, the compofition of the calamine from 

 Bleyberg, we fliall obtain the following refults ; 



Compound fait, ofcarbonateof zinc and hydrate of zinc 990. S 

 Water in the ftate of moifture - - . _ 2.5 

 Carbonate of lime and carbonate of lead - - 7,2 



1000.0 



It rnay be thought fome corroboration of the fyftem here 

 offeredi that, if we admit the proportions wUich it indicates^ 

 the remote elements of this ore, while they are regular parts 

 of their immediate produ6ls, by whofe fubfequent union this 

 ore is engendered, are alfo regular fradtions of the ore itfelf : 

 thus. 



The carbonic acid - - - =.~^ 

 The water _ - - - =6% 

 The calx of zinc - - - - =^ 



Hereby difplaying that fort of regularity, in every point of 

 view of the objed, which fo wonderfully charadlenfes the 

 works of nature, when beheld in their true light. 



If this calamine does confift of carbonate of zinc and hydrate 

 of zinc, in the regular proportions above fuppofed, little doubt 

 can exift of its being a true chemical combination of thefe two 

 ihatters, and not merely a mechanical mixture of them in a 

 pulverulent ftate ; and, if fo, we may indulge the hope of 

 fome day meeting with this ore in regular cryftals. 



If the theory here advanced has any foundation In truth, 

 the difcovery will introduce a degree of rigorous accuracy and 

 certainty into chemiftry, of which this fcience was thought to 

 be ever incapable, by enabling the chemift, like the geome- 

 trician, to redlify by calculation the unavoidable errors of his 

 G 2 manuai 



