g^i CHKMICAL ANALYSIS OF SOME CALAMINES. 



Eluclditionsof manual operations, and hy aiitliorifin;; him (o eliminate from 

 chemical theory, ^j^^ e.Tential elements of a compound, thofe produds of its 

 analyfis whofe quantity cannot be reduced to any admiffible 

 proportion. 



A certain knowledge of the exa6l proportions of the con- 

 ftituent principles of bodies, may likewife open to our view 

 harmonious analogies between the conflitutions of related 

 objects, general laws, &c. which at prefent totally efcape us. 

 In fbort, if it is founded in truth, its enabling the application 

 of mathematics to chemiftry, cannot but be produdive of 

 material refults *. 



3. By the application of the foregoing theory to the experi- 

 ments on the eledrical calamine, its elements will appear to 

 be. 



Quartz ----- -y 



Calx of zinc - -. - - - f 

 A fmall quantity of the calamine having efcaped the adion 

 of the vitriolic acid, and remained undecompofed, will account 

 for the flight excefs in the weight of the quarlz. 



4. The exhalation of thefe calamines at the blowpipe, and 

 the flowers which they diffufe round them on the coaU are 

 probably not to be attributed to a direfl volatilization of them. 

 It is more probable that they are the confequences of the dif- 

 oxidation of the zinc calx, by the coal and the inflammable 

 matter of the flame, its fublimation in a metallic fiate, and in- 

 ftantaneous recalcination. And this allernate reduclion and 

 combuflion, may explain the peculiar phofphoric appearance 

 exhibited by calces of zinc at the blowpipe. 



The apparent fublimation of the common flowers of zinc at 

 the inlJant of their produ6lion, though totally unfublimable 

 afterwards, is certainly likewife but a deceptions appearance. 

 The reguline zinc, vaporifed by the heat, rifes from the 

 crucible as a metallic gas, and is, while in this ftate, convert- 

 ed to a calx. The flame which attends the procefs is a proof 

 of it; for flame is a niafs of vapour, ignited by the produdion 

 of fire within itfelf. The fibrous form of the flowers of zinc, 

 is owing to a cryftallizalion of the calx while in mechanical fuf- 



* It may be proper to fay, that the experiments have been ftated 

 fredfely as they turned out, and have not been in the Itafl degru 

 hcjit to the fyftem. 



