the Attractive Powers of Mineral Acids, 59 
Hence we fee why horn filver can never be reduced by fixed 
alkalies without lofs, as Mr. margraaf has (hewn, 1 march, 
277. ; nor could it be decompofed at all, but that the a&ion 
of heat helps that of the alkali. 
It to a folution of fublimate corrofive oil of vitriol he added, 
a precipitation will appear; but, as Mr. bergman well 
remarks, this does not proceed from a decompofition, but from 
a fub ft rati ion of the water neceftary to keep the fublimate 
diffolved. 
If to a folution of vitriol of iron fome nitrous acid be added, 
it immediately becomes turbid, becaufe the nitrous acid dephlo- 
gifticates the calx of iron too much, but the addition of more 
acid reftores the tranfparency, as the dephlogifticated calx is 
ftill foluble by a greater quantity of acid. I omit a number of 
other curious phenomena, which are explicable on thefe prin- 
ciples. 
I have afligned in the foregoing table two different affinities 
to the vitriolic acid \yith regard to wifmuth, and alfo to the 
marine acid with regard to nickel and wifmuth. The firft 
fhews that which thefe acids bear to thole metals, when de- 
phlogifticated only by folution in thofe acids. The fecond 
number, that which the acids bear to them when more dephlo- 
gifticated, as they are, when difiolved in the nitrous acid. On 
the other hand, all the acids have lefs affinity to the calces of 
iron, zinc, tin, and antimony, when they are dephlogifticated 
to a certain degree ; but as I could give no criterion of this 
dephlogiftication, I did not attempt to indicate the diminution 
it caufes in the affinities of acids. 
