1 1 8 Dr. Kane's Contributions to the History 



Weight of a litre of vapour at zero cen-1 ,, , ^^ 

 .•1 I ^ »,^ . 1 ?"= .^'126 eram. 



ti</rade and 0-76 met. bar. press J " 



Specific gravity of vapour 4'*4065 — 



(No. 2.) Weight'of balloon with air 49-64-5 



Weight of balloon with vapour 46*938 



Excess =0*293 gram. 



Residual air =0 



Temperature of air 21^ cent. 



vapour 98 cent. 



Barometer 0*75 metre. 



Result: Weight of a litre 3*1279 gram. 



Specific gravity 2*408 — 



The theoretical density is 



4 volumes gaseous carbon = 3*3712 



10 hydrogen 0*6880 



3 oxygen 3*3078 



3 -f- 7*3670 = 2*4556 

 It is curious that the variation from theory in these deter- 

 minations lies in the opposite direction from what is usual, 

 and the complete coincidence of the two experiments proves 

 that the deviation results not from manipulation but from the 

 nature of the fluid itself. The simultaneous though trivial 

 excess in carbon induces me to attribute botli to the presence 

 of a trace of aldehyd, from the last portions of which, owing 

 to the great volatility of the formal, the latter can scarcely be 

 obtained free. 



The empirical formula of this body C4 H^q O3 allows of 

 many methods of considering its real nature. The first that 

 naturally occurs is that it was a higher degree of oxidation of 

 aether, a tritoxide of ethyle A E . O^; but although sensible of 

 the importance of this view, with respect to the alcohol and 

 methylene series, and generally to the theory of organic radi- 

 cals, I am of opinion that the balance of probability inclines in 

 favour of a different arrangement. 



When this fluid is brought into contact with potash or ba- 

 ryta, Dumas's pyroxylic spirit is formed, and formate of potash; 

 to illustrate this action we have only to consider that the com- 

 position of this fluid is C4 H^q O3, or 



3 atoms methylene asther = Cg Hjg O3 

 I atom formic acid = Cg Hg O3 



Cg H20 Og 



Dumas and Peligot had already proved formic acid to be 

 the product of the highest degree of oxidation of pyroxylic 



