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A chemical Analysis of some Calamines. By James Smithson, Esq. 

 F.R.S. Read November 18, 1802. [Phil. Trans. 1803, p. 12.] 



The uncertainty that has till now prevailed concerning the nature 

 and composition of the ores of zinc called Calamine, has induced our 

 author to enter upon the investigation now before us. In the first 

 part of the paper, we find the analysis of four kinds of calamines ; 

 the first from Bleyberg in Carinthia, the second from the Mendip 

 hills in Somersetshire, the third from Derbyshire, and the fourth an 

 electrical calamine from Regbania in Hungary. Referring to the 

 paper for the detail of the four processes there circumstantially de- 

 scribed, we must content ourselves with reciting here the results de- 

 duced from each of them. 



1000 parts of the Bleyberg ore were found to consist of 714 calx 

 of zinc, 135 carbonic acid, and 151 water. Some carbonate of lime 

 and lead were likewise found in it ; but these appeared to be mere 

 accidental admixtures, and in too small quantities to deserve notice. 



1000 parts of the Mendip ore consisted of 648 parts of .calx of 

 zinc, and 352 of carbonic acid, and yielded no water. 



In the Derbyshire ore were found 652 of calx of zinc, and 348 of 

 carbonic acid. 



And in the Hungarian ore, 683 of calx of zinc, 250 of quartz, 44 

 water : and here there moreover appeared a loss of 23, owing, no 

 doubt, to some defect in the manipulation. The water was by no 

 means considered as an essential part of this ore ; and hence the pro- 

 portions of the two other ingredients were as 739 to 261. 



In a second part of the paper, the author communicates some ob- 

 servations to which he was led by the uncertainty that still prevails 

 in our chemical researches, and the want of uniformity in the results 

 of the multitude of experiments that are daily made, which appear 

 to him to clash essentially with the simplicity of nature. When we 

 consider, he says, the simplicity found in all those parts of nature 

 which are sufficiently known to come within the reach of our obser- 

 vation, it appears improbable that the constituent parts of bodies, 

 which we consider as endowed with reciprocal affinities, should be 

 so loosely united as is often indicated by the most accurate analysis. 

 Hence he is led to conjecture, that in all chemical combinations, 

 those ingredients which are really essential to the compound are 

 but few in number ; that they are by nature certain aliquot parts of 

 the whole compound ; and that as the aliquot may be expressed by 

 fractions, the denomination of these fractions will always be a small 

 quantity, perhaps never exceeding the number 5. 



The author applies this theory to the above-mentioned experiments 

 on calamine ; and finding that, with a trifling correction, the results 

 coincide with this theory, he entertains sanguine hopes that future 

 investigations will finally establish it. If so, he thinks that the 

 discovery will introduce in chemistry a rigorous accuracy, of which 

 it has not hitherto been thought susceptible ; that it will enable the 

 chemist, like the geometrician, to rectify by calculation the unavoid- 



