44 .A/r. kir wan’s "Experiments and Obfervations on 
nitrous acid ; and alio thefe falts, together with cubic nitre 
and nitrous ammoniac, are decompofed by the marine acid, aa 
Mr. bergman and Mr. cornette have remarked : all which 
ihew, that thefe decompoiitions are the effect of a double affinity, 
or at leaf! of compound forces. I always fufpedted they aroi'e 
from the different capacities of thefe acids for elementary lire % 
but as the fubjedt appeared to me of importance, for greater 
certainty I made a feries of experiments which differ from 
thofe hitherto made in feveral refpedts, particularly in this, 
that no heat was applied, and the decompoiitions were difeo- 
vered, net by cryffallization, but by teffs. 
Firff, I procured equal weights of each of the mineral acids,, 
containing each the fame quantity of real acid ; and throwing- 
each fuddenly on an ounce of the fame oil of tartar, I had the: 
following refults, the temperature of all, before mixture,, being 
68° of Fahrenheit., i oo grs. of vitriolic acid, containing 
26,6 grs. of real acid projected on 480 of oil of tartar, raifed 
the thermometer to 13 8°.. 
10a grs. of fpirit of nitre, which alfo contained 26,6 grs.. 
real acid, projedted in the fame manner on 480 grs. of the 
fame oil of tartar, produced a heat of 120°. 
100 grs. of fpirit of fait, whofe fpecific gravity was 1,220, 
and which contained 26,6 gr,s. of real acid, projedted on the 
above quantity of the fame oil of tartar, raifed the thermo- 
meter from 69 to 1 29°. 
Hence it follows, that the vitriolic acid contains more fpeci-- 
fic hre, or at leaf! gives out more on uniting to fixed alkalies,, 
than either the nitrous or marine ; and, therefore, when the 
vitriolic acid comes in contadl with either nitre or fait of fyl- 
vius, its fire paffes iinto thefe acids, which are thereby rarefied 
to a great degree, and are thus expelled from their alkaline 
bafis. 
