the Attractive Powers of Mineral Acids . 40 
reafon why the nitrous acid, which fpecitically contains lefs 
fire than the vitriolic, gives out fo much, is, that its quantity 
in both thefe experiments is far greater than that of the vitri- 
olic, it being in the firft as 105 to 17 ; and in the fecond as 
1 58 to 1 7. 
For this reafon, to 60 grs. of fpirit of nitre, whofe fpecific 
gravity was 1,355, I added 1000 grs. of water, and into this 
dilute acid I put 60 grs. of tartar vitriolate, which contained 
exactly the fame quantity of acid as the 60 grs. of fpirit of 
nitre. After eight days the tartar vitriolate was almod intirely 
diffolved, yet I could perceive no fign of its decompofition, 
and after evaporation no nitre was found. Hence I conclude, 
that the nitrous acid can never decompofe tartar vitriolate 
without the afliflance of heat, but when its quantity is fo 
great that it contains confiderably more fire, and by the acd of 
folution is determined to give out this fire. The decompofition 
of Glauber’s fait and vitriolic ammon. (neither of which, as 
Mr. bergman obferved, is ever total) maybe explained in the 
fame manner ; whereas the vitriolic, ever fo dilute, decom- 
pofes both nitre and nitrous ammoniac totally. Tartar vitriolate 
is alfo decompofed by the marine acid, though very flowly, for 
the dime reafon, and in the dime circumdances, as it is decom- 
pofed by the nitrous acid, as appears by the following experi- 
ments. Into 400 grs. of fpirit of fait, whofe fpecific gravity 
was 1,220, I put 60 grs. of tartar vitriolate. The thermo- 
meter was not in the lead affedled, and the fait didolved verv 
flowly. To try whether the vitriolic acid was difengaged, I 
added fome pulverifed bifmuth ; in twelve hours part of the 
bifmuth was diffolved, and could not be precipitated by 
the affudon of water, a flgn that it was held in folution 
by the compound acid, which alone hath the property of 
5, preventing 
