NITRIC ACID. 
that its own water of crystallization is suffi- 
cient to dissolve it at a boiling heat. It is 
likewise soluble in less than its weight of 
alcohol. By evaporating the aqueous solu- 
tion to dryness, continuing the heat till the 
nitrate fuses, keeping it in this state five 
or ten minutes, and then pouring it into 
an iron pot previously heated, we obtaiil 
Baldwin’s phosphorus. This, which is, per- 
haps, more properly nitrite of lime, being 
broken to pieces, and kept in a phial close- 
ly stopped, will emit a beautiful white 
light in the dark, after having been exposed 
some time to the rays of the sun. At pre- 
sent no use is made of this salt, except for 
drying some of the gases by attracting their 
moisture ; but it might be employed instead 
of the nitrate of potash for manufacturing 
aqua fortis. 
The nitrate of ammonia possesses the pro- 
perty of exploding, and being totally de- 
composed, at the temperature of ' 600 ’^} 
whence it acquired the name of nitrum 
flammans. The readiest mode of prepar- 
ing it, is by adding carbonate of ammonia to 
dilute nitric acid till saturation takes place. 
If this solution be evaporated in a heat 
between 70° and 100°, and the evaporation 
not carried too far, it crystallizes in hex- 
aedral prisms terminating in very acute py- 
ramids; if the heat rise to 212°, it will 
afford, on cooling, long fibrous silky crys- 
tals i if the evaporation be carried so fqr 
as for the salt to concrete immediately on 
a glass rod by cooling, it will form a com- 
jiact mass. According to Mr. Davy, these 
differ but little from each other, except in 
tlie water they contain, their component 
parts being as follows : 
Prismatic I 
Fibrous > 
Compact 3 
contains 
of acid 
69.5 ) 1 
r 18.4 1 i 
C 12.1 
72.5 V ammonia < 
J 19.3 V water - 
< 8.2 
74.5 ) ( 
[19.8) 
C 5.7 
All tliese are completely deliquescent, but 
they differ a little in solubility. Alcohol 
at 176° dissolves nearly 90.9 of its own 
weight. 
The chief use of this salt is for affording 
nitrous oxide on being decomposed by heat. 
See nitrous oxide, under the art. Gas. 
Nitrate of magnesia, magnesian nitre, 
crystallizes in four-sided rhomboidal prisms, 
with oblique or truncated summits, and 
sometimes in bundles of small needles. Its 
taste is bitter, and very similar to that of 
nitrate of lime, but less pungent. It is fu- 
sible, and decomposable by heat, giving out 
first a little oxygen gas, then nitrous oxide, 
and lastly nitric acid. It deliquesces slow- 
ly. It is soluble in an equal weight of cold 
water, and in but little more hot, so that 
it is scarcely crystallizable but by sponta- 
neous evaporation. 
The two preceding species are capable 
of combining into a trijile salt, an ammo- 
niaco-magnesian nitrate, either by uniting 
the two in solution, or by a partial decom- 
position of either by means of the base of the 
other. This is slightly inflammable when 
suddenly heated : and by a lower heat is 
decomposed, giving out oxygen, azote, more 
water than it contained, nitrous oxide, and 
nitric acid. The residuum is pure mag- 
nesia. It is disposed to attract moisture 
from the air, but is much less deliquescent 
than either of the salts that compose it; 
and requires eleven parts of water at 60° 
to dissolve it. Boiling water takes up 
more, so that it will crystallize by cooling. 
It consists of 78 parts of nitrate of magnesia 
and 22 of nitrate of ammonia. ^ 
From the activity of the nitric acid as a 
solvent of earths in analyzation, the nitrate 
of glucine is better known than any other of 
tlie salts of this new earth. Its form is 
either pulverulent, or a tenacious or ductile 
mass. Its taste is at first saccharine, and 
afterward astringent. It grows soft by ex- 
posure to heat, soon melts, its acid is de- 
composed into oxygen and azote, and its 
base alone is left behind. It is very solu- 
ble and very deliquescent. 
Nitrate, or rather superni'trate, ofalumine, 
crystallizes, though with difficulty, in thin, 
soft, pliable flakes. It is of an austere and 
acid taste, and reddens blue vegetable co- 
lours. It may be formed by dissolving in 
diluted nitric acid, with the assistance of 
heat, fresh precipitated alumiue, well wash • 
ed but not dried. It is deliquescent, and 
soluble in a very small portion of water. 
Alcohol dissolves its own weight. It is 
easily decomposed by heat. 
Nitrate of zircone was first discovered 
by Klaproth, and has since been examined 
by Giiyton-Morveau and Vauqttelin. Its 
crystals are small, capillary, silky needles. 
Its taste is astringent. It is easily decom- 
posed by fire, very soluble in water, and 
deliquescent. It may be prepared by dis- 
solving zircone in strong nitric acid ; but 
like the preceding species, the acid is al- 
ways in excess. 
