58 JAMES SMITHSON AND HIS BEQUEST. 



phurio acid, and the action of heat, 1,000 parts of them were found to 

 contain, of carbonic acid 348, of oxide of zinc 652. 



The electrical calamine, which Mr. Smithson examined, was from Reg- 

 bania, in Hungary. It was in the form of regular crystals ; the specific 

 gravity of which was 3.434. 



They became electrical by heat, and when exposed to the flameof the 

 blowpipe decrepitated and shone with a green light. The electrical cala- 

 mine differs materially in composition from the other specimens, in being 

 formed chiefly of quartz and oxide of zinc, which, according to the author, 

 are in chemical union. One thousand parts of it gave 250 parts of quarte, 

 683 of oxide of zinc, and 44 of water; the loss being 23 parts. 



From his series of experiments on the calamines, Mr. Smithson has 

 been able to deduce, with a considerable degree of accuracy, the compo- 

 sition of sulphate of zinc, which, when free from combined water, he 

 considers as composed of equal parts of sulphuric acid and oxide of zinc. 



In reasoning generally upon the constitution of salts of zinc, Mr. Smith- 

 son offers some new observations in relation to afi&nity ; and he thinka 

 that the proximate constituent parts of bodies are not absolutely united 

 in the remote relations to each other, usually indicated by analyses, but 

 that they are universally very considerable parts of the compound, prob- 

 ably seldom less than 2. He applies this theory in accounting for the 

 presence of water in the calamine of Bleyberg, in which there is not suf- 

 ficient carbonic acid to saturate the oxide of zinc ; and he considers this 

 ore as probably composed of a peculiar combination of water with the 

 oxide of zinc, which he names hydrate of zinc, and of carbonate of zinc 

 to each other in the proportions of 3 to 2. 



All the calamines, when long exposed to the heat of the blowpipe, are 

 dissipated, with the production of white flowers. This circumstance, 

 the author thinks, ought not to be attributed to an immediate volatiliza- 

 tion of the oxide of zinc, but rather to the deoxidation of this substance 

 by the charcoal and combustible matter of the flame, and the consequent 

 immediate sublimation and combustion of the metallic zinc, to which 

 combustion the phosphorescence of calamines under the blowpipe may 

 be owing. 



The fibrous form of the flowers of zinc, produced during the action of 

 the blowpipe upon calamine, Mr. Smithson attributes to the crystalliza- 

 tion taking place during their mechanical suspension in the air; and he 

 thinks that the fluid state is not at all necessary to the production of 

 crystals, and that the only requisite for this operation is a freedom of 

 motion in the masses which tend to unite, allowing them to obey that 

 sort of polarity which occasions them to i^resent to each other the parts 

 adapted to mutual union.* 



NOTE 5. 



ILLUSTRATIONS OF PRESENTATION OF BOOKS BY SOIENTIFIO AUTHORS 



TO SMITHSON. « 



**Mr. Smithson. Hommage respectueux de I'auteur." 



Nouveau syst^me de min6ralogie. Par J. J. Berzelius. Paris, 1819. 

 "Mr. Smithson. Hommage de I'auteur, Gay-Lussac." 



M6moire sur I'iode. 1814. 



* Journal of the Royal Institution of Great Britain, 1802, Vol. 1, p. 299. 



