340 ON THE PRODUCTION OF TURFUROL. 
mixture becomes clear on heating. Tlie specific gravity of 
the cold saturated solution is 1.01.32. 
The specific gravity of the vapour of furfurol was care- 
fully determined by the method of Dumas. A little patch 
of brown matter, the result of trifling decomposition, re- 
mained in the globe, but its weight must have been almost 
inappreciable. The following are the details of the expe- 
riment: 
Weight of globe, 13 47.63 grains. 
Temperature of air, 64° Fahr. 
Barometer, 30 inches. 
Temperature of oil-bath, 3S0° Fahr. 
Weight of globe after experiment, 1356. grains. 
Capacity of globe, 23.13 cubic inches. 
Residual air-bubble, .12 cubic inch. 
Specific gravity of vapour, 3.493. 
From this it follows that the formula for furfurol should 
be the very simple one, C^H^O^, and not the triple of this, 
as formerly assumed, since every volume of vapour will be 
thus represented : 
5 volumes hypothetical carbon-va- 
pour* 4183x5=2.0915 
2 volumes hydrogen . . . .0693x2= .1386 
1 <^ oxygen, . . . ==1.1057 
I vapour of furfurol . 3.335S 
Pharm. Journ, 
* Oa the supposition that carbonic acid contains equal volumes of 
oxygen and carbon-vapour, condensed to one-half. 
