with the Nitric and Nitrous Acids. 345 
- at first as pure nitrite ; and this appeared so much the more pro- 
bable, as they presented to the eye all the characters of a homo- 
geneous substance, and as they were'formed in the midst of a 
great mass of liquid; but ulterior experiments convinced me 
that this salt was formed of nitrite and nitrate, and that it was 
a kind of double salt with two acids. I was led to this singular 
result by the decomposition which the carbonic acid made it 
undergo. 
41. In order to show more evidently the difference of these 
crystals from the nitrite coming from the subnitrite, 1 shall sup- 
pose them formed of Nitrous acid ........ 0°887 gr. 
OXTGT) ciate sors oe ae F000" 
Water a. sols oo 5552 ORS 
5000 
I passed into the solution of these five grammes a stream of 
carbonic acid, and I separated from it 2°20 gr. of oxide: there 
remained therefore in the liquor 1:80 gr. of base and 0°887 of 
acid: this report gives for 100, 
AGG DS. haa dena ro) aoe 
Base. sae s'e nots» OOVS 
In this experiment the salt had been dissolved in nine decilitres 
of water. In another I put the same salt in powder in three de- 
cilitres of water, and obtained by the carbonic acid 2°21 gr. 
of base. (1 had made this experiment with a view to ascertain 
if the quantity of water had any influence on the quantity of 
oxide precipitated.) A third and fourth experiment gave me 
2°20 gr. and 2°23. They concur therefore perfectly in proving 
that the carbonic acid separates more base from the nitrite pre- 
pared with the acid nitrate of lead and the metal than from 
that obtained from the subnitrite. 
42. The solution precipitated by the carbonic acid evaporated, 
gave off nitrous acid, and deposited upon cooling yellowish white 
scales: the mother-water of these scales, concentrated, gave 
small white needles ; and the mother-water of these needles; 
spontaneously evaporated, yellow crystals resembling by their 
form the acid nitrate of lead. Now as the nitrite coming from 
the subnitrite only gives, when we decompose it by the carbonic 
acid, yellow nitrite and nitrous acid, and not white salt, we must 
~ eonclude that the nitrite prepared by M. Proust’s process differs 
from it in its composition. 
-43. I examined in the first place the white needles, and after 
having crystallized them several times I found them similar 
* The proportion of the base had been determined by experiment, and the 
water aud the acid had been calculated fPom the analysis of the nitrite 
(31). . 
to 
