On the Atomic Weights of Bodies. 



251 



Natural philosophers in their turn have also overlooked it, 

 because in their lectures and works, the public of the pre- 

 sent day only require such surperficial notions as can be 

 readily grasped by a common mind without any exertion. 

 In all this we see nothing exceptional ; like all those who 

 penetrate into the depth of science, he has been unknown to 

 the multitude. But the applause of some men of eminence 

 should make ample compensation. In such matters we 

 ought not to count votes, it is wiser to weigh them. 

 {To be continued.) 



Article II. 



Observations on the Atomic Weights of Bodies. By Thomas 

 Thomson, M. D., F.R. S. L. & E., Regius Professor of 

 Chemistry in the University of Glasgow. 



{Concluded from page 193.) 



It seems to be a general law, that the specific gravity of a 

 gas is equal to its atomic weight multiplied by some sub- 

 multiple or multiple of the specific gravity of oxygen gas. 

 This will appear from the following tables. 



I. Gases whose specific gravity = their atomic weight 

 x 0-2777 or ith the specific gravity of oxygen gas. 



I Specific Gravity, 

 Atomic By experi- By calcula- 

 weight. 



Ammonia, . . . 

 Deutoxide of azote, 

 Muriatic acid, . . 

 Hydriodic acid, . 

 Hydrobromic acid, 

 Calomel, 



2-125 

 3-75 



4-625 

 15-825 

 10-125 

 29-5 



0-59023* 

 l-04096f 

 1-2844$ 

 4-4093 § 



8-35|| 



0.59027 



1-04166 



1-28472 



4-40972 



2-8125 



8-1944 



* This is the mean between the specific gravity found by Sir II. Davy and my- 

 self, — See Annals of Philosophy, xvi. 175. 

 t By my experiment. — Ibid. p. 172. 

 } By my experiment. — Ibid. p. 176. 



4 Mean of the determination of Gay Lussac and my own. — Ibid. p. 264. 

 || Mitscherlich. — l'oggendorff 's Annalen, xxv. 2'-';!. 



