the Attractive Powers of Mineral Acids. 5 y 
mineral acids to metallic tubftances to be as above, all double 
decompofition in which only halts, containing thefe acids united 
to alkaline terrene or metallic bafes, are concerned, admit of 
an eafy explanation ; nay, I am bold to fay, they cannot other- 
wife be explained. Thus if a folution of tartar vitriolate, and 
of filver in the nitrous acid, be mixed in proper proportions 
(which is always to be underflood), nitre and vitriol of five? 
will be formed, and this latter for the moft part precipitated. 
Quiefcent affinities. 
Nitrous acid to filver 
Vitriolic acid to vegetable alkali 
Sum of the quiefcent 
375 
2I 5 
59 0 
Divellent affinities. 
Nitrous acid to vegetable alkali 
Vitriolic acid to filver 
Sum of the divellent powers 
21 5 
39 ° 
60c 
So alfo if, inflead of a folution of tartar vltriblate, that of 
Glauber’s flit, or of vitriolic-ammoniac, or felenite, Epfom, 
or allum, be ufed ; for in all thefe cafes the balance is con- 
ifantly in favour of the divellent powers, yet the folutions of 
felenite and allum produce but a flight precipitation. 
I alfo found, that the folution of lllver is precipitated by the 
vitriolic folutions of iron, copper, tin, and probably by many 
other vitriolic folutions, if for no other reafoti at leaft for this, 
that they constantly contain an excefs of acid ; but if a fatu- 
rate folution of filver be mixed with a very faturate folution of 
lead or mercury in the vitriolic acid, the filver will not be pre- 
cipitated, as I have obferved ; and in both cafes the balance is 
in favour of the quiefcent affinities. 
The nitrous folution of filver is alfo decompofed, and the 
filver precipitated bv all mart no neutral falts, whether the balls 
be alkaline, terrene, or metallic, as I have experienced, and 
Vol, LXXIII. I thefe 
