vegetable and animal substances. 465 
even cloud of chloride is produced. But 5 grains of indigo, 
prepared from the de-oxidized solution of the dyer's vat, and 
freed from its lime and resin by the successive application of 
dilute muriatic acid and alcohol, gave 5 cubic inches of mu- 
riatic acid gas when heated along with 150 grains of calomel. 
Here we have a quantity of gas equivalent to 2j cubic inches 
of hydrogen. By means of peroxide of copper, however, 
nearly 4 times the above quantity of hydrogen may be ob- 
tained from the same weight of indigo. 
I shall now give in detail, one example of the mode of 
computing the relation of the constituents from the experi- 
mental results, and shall then state the other analyses in a 
tabular form, subjoining a few remarks on the habitudes of 
some peculiar bodies. 
1.4 grains of sulphuric ether, specific gravity 0.70, being 
slowly passed in vapour from the glass bulb through 200 
grains of ignited peroxide of copper, yielded 6.8 cubic inches 
of carbonic acid gas at 66 c F. which are equivalent to 6.57128 
of dry gas at 6o°. This number being multiplied by 0.127 = 
the carbon in 1 cubic inch of the gas, the product 0.8345256, 
is the carbon in 1.4 grains of ether; and 0.8345256 xf = 
2.2254 = the oxygen equivalent to the carbonic acid. The 
tube was found to have lost 4.78 grains in weight, 0.1 of 
which was due to the hygrometric moisture in the oxide, and 
1.4 to the ether. The remainder, 3.28, is the quantity of 
oxygen abstracted from the oxide by the combustible ele- 
ments of the ether. But of these 3.28 grains, 2.2254 went 
to the formation of the carbonic acid, leaving 1.0546 of 
oxygen, equivalent to 0.1318 of hydrogen. Hence, 1.4 ether, 
by this experiment, which is taken as the most satisfactory of 
mdcccxxii. 3 O 
