7° Dr. de Crell on the Decomposition 
let it evaporate, and treated it as described above, Exp. xxn. — 
xxx. 
Exp. liii. I obtained a white salt, a , and some coal, 6, (which 
deflagrated briskly with nitre, ) in nearly the same proportions 
as throughout the series of experiments described from Exp. 
xxii. to xxxm. which I will not repeat, on account of the little 
variety observed in them ; one of them, however, deserves to 
be distinguished from the rest. 
Exp. liv. I put six grains of the coal, b, (of Exp. liii.) in 
three drams of common muriatic acid, and digested them for 
two days, till the acid had gradually evaporated. I then added 
one dram of the same acid, with one scruple of nitric acid, and, 
when they had evaporated, boiled the residuum full half an 
hour in distilled water. By this process, I obtained a red solu- 
tion ; and, having saturated it with mild alkali, a sort of skin 
rose to the surface, with some small pieces of a fat slippery 
substance, a. A considerable quantity of loose earth, b , was 
also precipitated, of a light brown colour. 
Exp. lv. On throwing the floating pieces, a, [Exp. liv.) 
into a solution of caustic alkali, they dissolved; the solution 
had a reddish-brown colour. 
Exp. lvi. With the same solution of caustic alkali, I co- 
vered the light brown earth of Exp. liv. As the solution 
changed its colour to a reddish brown, the earth gradually be- 
came perfectly white. 
Exp. lvi i. To observe the affinity of other acids to the seda- 
tive salt, I poured six drams of nitrous acid upon two drams of 
the salt, with ten drams of the forementioned oxygenated muri- 
atic acid ; digested the mixture, and distilled it, in twenty-four 
