Mons. R. Piria on the Combinations of Salicyle, 217 
is a yellow crystalline body, soluble in alcohol and jether, 
nearly insoluble in water; the addition of weak alkalies causes 
the disengagement of ammonia; by heating it in an acid fluid 
it is decomposed, a salt of ammonia being formed, and chlo- 
ride of salicyle being set free. Chlorosamide consists of 
Atoms. 
Carbon . . . 
U = 
84? 
56*52 
Hydrogen . 
5 
5 
3*30 
Oxygen . . . 
2 
16 
10*57 
Nitrogen . . 
4 
5 
18-4 
6*23 
Chlorine . . 
1 
36 
23*38 
Atomic weight. . . 
159-4 
100 
When gaseous ammonia is made to act on bromide of ben- 
zoyl, a compound called hromosamide results ; its composition 
is identical with chlorosamide, with the substitution of the 
chlorine by its equivalent of bromine. 
Action of the air on Salicide of Potassium, 
When salicide of potassium in a perfectly dry state is ex- 
posed to the air, or to an atmosphere of oxygen gas, it under- 
goes, as has been already observed, no obvious change; but 
if this salt be previously moistened, it, by a similar exposure, 
alters in colour, its surface becomes covered with green 
specks, and it darkens in hue until the whole mass becomes 
completely black. If the moist salicide of potassium be placed 
in a receiver of oxygen gas inverted over mercury, the latter 
will be observed to rise rapidly in the glass, from the absorp- 
tion of its gaseous contents. When the black, changed, salt 
is digested in water, a certain portion dissolves, and a soot- 
like powder is left ; this should be collected, washed, and 
dried. This black compound dissolves readily in alcohol and 
aether, but is insoluble in water; it dissolves in alkaline solu- 
tions, forming saline compounds, from which the black pow- 
der is thrown down unchanged by acids. This substance 
appears to possess properties of a decidedly electro-negative 
character, and from this circumstance, as well as from its co- 
lour, it has been termed melanic acid^ a name unhappily chosen, 
as it has already been applied to an ingredient in certain mor- 
bid animal secretions. 
Melanic acid decomposes alkaline carbonates, forming saline 
combinations, attended with the evolution of carbonic acid 
gas. When heated this acid burns slowly, but without flame, 
and leaves no fixed residue. 
Melanate of silver was prepared by precipitating a solution 
of melanate of ammonia by nitrate of silver ; the precipitate 
