OXYGEN AND HYDROGEN GASES. 



to show that the atomic weight of oxide of zinc 

 is 5&5, and that it is a compound of 4'2<5 zinc 

 and 1 oxygen. And this being the only object 

 in^view, we need not at present proceed any far- 

 ther. 



SECT. II. 



OF THE SPECIFIC GRAVITY OF OXYGEN GAS. 



VARIOUS statements of the specific gravity of 

 this gas have been published by different che- 

 mists. The following table exhibits those which 

 have been generally considered the most to be 

 depended on. 



g!arities of 1 ' 114 Saussure, Ann. de Chim. LXXI. p. 269. 



oxygen gas. 1*103 . Biot and Arrago, Mem.de 1'Institut. 1806, 



p. 320. 



1-089 Allen and Pepys. Phil Trans. 1807. 

 1-1117 Thomson, Annals of Philosophy, XVI. p. 1 63, 

 1-1026 . Berzelius and Dulong, Ann. de Chim. et de 

 Phys. XV. 386. 



It would be impossible to decide which of 

 these determinations deserves the preference. 

 The experiments were all made with care, and 

 no doubt, sufficient precautions were taken to 

 have the gas in a state of purity. I shall there- 

 fore proceed to relate the attempts which I have 

 made to determine the specific gravity of oxy- 

 gen gas in quite a different way. 



