or THE DESTEHCTIVE DISTILLATION OE BOGHEAD COAL. 
457 
Temperature of air . 
Pressure . . . . 
Capacity of balloon . 
Eesidual air . . . 
The formula C^® requires — 
20 volumes carbon vapour 
44 volumes hydrogen . . . 
Experiment. Eeankland. 
4-930 4-899 
21 ° 
767-3 mm. 
283-5 cub. cent. 
'5 cub. cent. 
0-8290.20 
0-0692.44 
Wtjrtz. 
4-956 
=16-580 
= 3-045 
19-625 
=4-906 
Theory. 
4-906 
The boiling-point of amyle, according to the most recent experiments on the subject*, 
is 158°, which agrees quite as nearly as could be expected with the above result. The 
density of the fluid was found to be (at 18°) 0-7365. Feaj^klajstd found it 0-7704 at 11°, 
and WuETZ 0-7413 at 0°. 
When Boghead amyle is cohobated with monohydrated nitric acid for some days, a 
large quantity of a nitro-acid is formed, which yields a silver salt of very sparing solu- 
bility. This acid will be described in a future communication, it being my intention to 
compare the products of the action of oxidizing agents on the radical from the Torbane- 
hill distillate, with those from amyle prepared by the action of sodium on the iodide. 
Caproyle. 
This radical was first isolated by Messrs. Beaziee and GosSLETHf in the course of 
their researches on caproic and oenanthylic acids ; they obtained it by the electrolysis of 
cenanthylate of potash. Eemembering that, as obtained by them, it had a boiling-point 
of 202°, I commenced in searching for it by taking the vapour-densities of the fractions 
a little above and below that point, and obtained the numbers annexed : — 
Excess of weight of balloon 
Temperature of vapour . 
Temperature of air . . 
Pressure 
Capacity of balloon . . 
Eesidual air .... 
Density 
Boiling-point, 
196° to 199°. 
-8855 grm. 
230° 
15° 
739-4 mm. 
322-5 cub. cent. 
4- 0 cub. cent. 
5- 74 
Boiling-point, 
202° to 208°. 
•6680 
233° 
14° 
760-2 mm. 
225 cub. cent. 
-5 cub. cent. 
6-03 
The hydrocarbon from the Boghead naphtha, of which I was in search, boiled therefore 
* "WuETZ, Ann. de Chimie et de Phys. 2™® serie, tome xliv. p. 282. 
t Quarterly Journal of tlie Chemical Society, vol. iii. p. 226. 
3o 
MDCCCLVII. 
