258 



Dr. Thomas Thomson's Observations 



10 atoms Zoisite, 



TABLE IX. 



Specific 

 heat. 



0-194$ 



0-302+ 



0-2137+ 



0-200+ 



0-1926+. 



0-1976;}: 



0-1861$ 



0-1961+ 



Product. 



12-716 

 1 3-171 

 2-45 

 3-25 

 4-67 

 5-73 

 6-839 

 6-814 



The specific heats marked by an asterisk (*) were determined by Avogadro. — 

 See Ann. de Chim. et de Phys. lv. 80 and lvii. 113. and Records i. 108, and ii. 

 34. Those marked t were determined by Dulong and Petit. — See Annals of 

 Philosophy, xiii. 164. and xiv. 189. Those marked % were determined by 

 Neumann. — See Poggendorff 's Annalen, xxiii. 1. Those marked § were deter- 

 mined by Dalton. — See New System of Chemical Philosophy, i. 62. Those 

 marked || by Lavoisier and Laplace. Those marked (c) by Crawford. — See table 

 at the end of his Treatise on Animal Heat. Those marked (d) by Dupretz. — 

 See Ann. de Chim. et de Phys. xxiv. 328. 



The first table exhibits the atomic weights and the specific 

 heats of 26 simple bodies, together with the products ob- 

 tained by multiplying the atomic weight and specific heat 

 of each body into each other. This table, by means of 

 horizontal lines, is divided into 6 compartments. Of these 

 we shall consider the third group first, which includes 16 dif- 

 ferent bodies or almost two-thirds of the whole. The product 

 of the atomic weight of these bodies into their respective 

 specific heats gives numbers which do not absolutely coincide 

 with each other ; but which, if we leave out the number 

 for azote, approach each other pretty nearly, and the mean 

 of the whole gives the number 0-375 as the product of the 

 atomic weight and specific heats multiplied into each other. 

 In all of these bodies then we may conclude the same 

 quantity of heat exactly is attached to each atom ; and the 

 reason why their specific heats appear different is that the 

 atoms of the respective bodies differ from each other. But 

 the specific heat of each atom of all these bodies is abso- 

 lutely the same. 



