the Attractive- Powers ef Mineral Acid:.. 
lofs of phlogiflon, ioo grs. of pure lilver fhould lofe -15,3; 
ancl by the above table 1 5,3 grs. of filver fhould contain 
0,945 of a grain of phlogiflon. Let us now fee whether this 
quantity of phlogiflon correfponds with that which 100 grs. of 
pure lilver really lofe by folution in nitrous acid. 100 grs. of 
pure filver afford, as already {aid, 1 4 cubic inches of nitrous 
air, which, by ray computation, contain 0,938 of a grain of 
phlogiflon, which differs from 0,945 only by The un- 
reduced part of the lilver was 15,3 grs . ; and, by calculating 
what it fhould be by reafon of the lofs of the phlogiflon con- 
tained in the nitrous air, it would amount to 14 and _?_ 0 ths of a 
grain, a difference certainly immaterial. 
In this experiment, only as much of the lilver fublimed as 
could not regain phlogiflon ; the remainder regained it from 
the nitrous air abforbed by the folution, and alio from that 
which remained united to the acid and calx. If this were not 
lb, 1 do not fee why the whole of the Lilver would not fublime. 
Again: Dr. priestley having feveral times diflolved mer- 
cury in the nitrous acid, and revivified it by diflilling over that 
acid, conflantlv found a confid'erable proportion of it unre- 
duced. To try whether that proportion correfponded with mv 
calculation, I have examined; the experiment which he mad* 
with mofl care, and which is to be found in his 4th vol. p. 
262. We there find, that having diflolved 17 dwts* 13 grs. -■ 
3,21 grs. of mercury in nitrous acid, i 4 dwt. that is, 36 grs. 
remained unreduced. Now, according to my calculation, 56 
grs. fhould remain unreduced ; for 100 grs. of mercury afford 
12 cubic inches of nitrous air; therefore 3.2 1 grs. fhould afford 
38,52, which contain 2,58 grs. of phlogiflon, and if (accord- 
ing to the table) 4,56 grs. of phlogiflon be neceffary to metallize 
xoogrs. of mercury, 2,58 will be neceffary to metallize 56 grs. 
