10 History of physical Science from [July, 



the readers of the Annals of Philosophy, I consider it as unne- 

 cessary to state them here. 



(Gilbert's Annalen der Physik, liv. 169.) 



These specific gravities approach very nearly those which I 

 have adopted in the last edition of my System of Chemistry. 

 Hydrogen, and oxygen, and chlorine, are the very same that had 

 been previously assigned by Dr. Prout. I have myself no doubt 

 whatever of their accuracy ; and suspect that Meinecke has been 

 influenced by Dr. Prout's paper, though he has taken no notice 

 of it. Meinecke adds some further reason for considering the 

 specific gravity of hydrogen as only one sixteenth of that of 

 oxygen. Dr. Prout's arguments are sufficiently strong to con- 

 vince every person who will take the trouble to examine them, 

 and is capable of understanding them. Some additional evi- 

 dences are given in the paper at present before me. I may 

 notice the specific gravity of steam, as determined by Gay- 



