NIT 
The firft column of this table fhews the number of atoms 
§ to the experiments of 
cid an 
the real acid or wat 
point, which may be denominated the poiut of mutual fatu- 
ation 
The acid of this ftrength has very curious properties, on 
which Dalton makes fome ingenious obfervations. Proutt 
has ftated, that an acid of the ftrength of 1.48 gives no more 
effervefcence with tin than it does with fand. When metals, 
ammonia, are a€ted upon by nitric acid; 
thefe, I fuppofe, are fuch as decompofe both the water and 
i n from both. The metal, under 
e, combines with 3 atoms of oxygen, 
while the nitrogen and the hydrogen torm amrronia. If the 
acid conlifted of 4 of real acid to 2 of water to 
d be fet free, which would dilute the remaining 
acid, and thus facilitate the procefs. 1f, however, the acid 
and water were as 2 to 3, then an atom of nitric acid, and an 
lace; but in the inftance with 2 of acid to 
water, all the produéts will be difpofed of in forming nitrat 
of ammonia, and reducing the acid to the ftrength of 
acid to 2 of water, during which change no effervefcence 
will take place. This view of the fubjet is very ingenious, 
and fully explains the phenomena attendant on the oxy- 
dation of thofe metals which caufe the formation of am- 
with oxygen, but 
with fuccefs. This 
mpound is formed, which, according to the 
opinion of Mr. Dalton, confifts of 1 atom of nitrogen with 
NIT 
which the oxygen is in excefs, is facilitated by the change 
In 
7 
= 
° 
oO 
na 
The combinations of nitric acid 
with the different faline bafes, are called nitrats. 
Irric, and Nitrous Acid, in the Materia Medica. 
The nitric acid of the London Pharmacopeia is prepared by 
mixing nitrat of potafh dried and fulphuric acid, of each two 
pounds, in a glafs retort ; and diftilling the nitric acid from 
a fand-bath, until red vapours are produced ; then add an 
ounce of dried nitrat of potafh, and re-diftil the acid ina 
fimilar manner. ‘The {pecific gravity of this acid is to that 
of diftilled water as 1.500 to 1.000 apiece of lime. ftone 
be immerfed in a fluid-ounce of it diluted with water, feven 
drams ought to be diffolved. According to the dircétions 
of the Edinburgh Pharmacopeia, any quantity of nitrous 
acid is put into a retort, and having fitted a receiver, a ver 
e {pecific gravity of this acid is to that of diftilled 
water as 1.550 to 1.000. Dublin Pharmacopeia orders 
fix pounds of nitrat of kali to be mixed with four pounds 
by weight of fulphuric acid, and then difti'led unii the 
refidue becomes dry. The fpecific gravity of this acid is to 
that of diltilled water as 1.500 to 1.0C0. 
In performing thefe operations, it is advifable to ufe 
Woulte’s apparatus, or a range of two or three globular 
receivers, the laft of which fheuld contain a {mall portion of 
order to prevent the nitrous oxyd from come 
the condenfed acid in the receiver, deepening 
