151 
Rolling these leads into thin sheets decreased the solvent 
action, except in one case, No. 2 Sample with Ammonium 
Nitrate, when the action was not materially influenced. 
Table X. 
Experiments carried out in Beakers ( 500 cb . c . liquid in each), 
LOOSELY COVERED WITH POROUS PAPER. 
Sample No. 1. 
Surface 
Lead dissolved, 
Salt. 
Grams 
of Lead. 
Nature of Lead. 
in Mgms., after 
per litre. 
sq. cm. 
6 days, 15 days. 
Water 
— 
... 50 . 
..As purchased.... 
. 0-3 ... 0*3 
Potassmm Nitrate.. 
. 0-20 
... 50 
• * 99 • 
.. 0-3 ... 0-4 
Ammonium „ 
0-20 
... 50 . 
. 0*3 ... 0-4 
Water 
— 
... 50 . 
..Polled out till' 
much thinner ^ 
■ trace... trace 
Potassmm Nitrate.. 
0-20 
... 50 . 
. . 
.trace... trace 
Ammonium „ 
. 0.20 
... 50 . 
• • 99 • 
..trace... trace 
Sample No. 2 . 
Water 
. — 
... 50 . 
..As purchased... . 
..trace 
Potassium Nitrate, , 
. 0-20 
... 50 
♦ • 99 • 
..trace 
Ammonium „ 
. 0-20 
... 50 
• • 99 • 
..trace 
Water 
— 
... 50 
..Polled out till' 
1 trace 
much thinner 
Potassium Nitrate.. 
. 0-25 
... 50 
. . 99 . 
..trace 
Ammonium „ 
. 0-25 
... 50 
• • 99 
..trace 
In these cases rolling also tended to decrease solvent 
action. I hope to continue these experiments, and to lay 
the results before the Society at another time. 
18, As a general rule I observed that the greater the quan*> 
tity of deposit upon the lead the smaller was the quantity 
of lead in solution. The deposit always consisted appar- 
ently of the same salt, and appeared as light shining crystals, 
sometimes arranged in beautiful feathery forms upon the 
surface of the slips of lead. Analysis shewed that this salt 
was of the same composition as that noticed several years 
ago by Miller, viz., 2PbC08, Pb(OH) 2 . 
14. I wish to make a correction with regard to the action 
of dilute solutions of Calcium Chloride upon lead. In part 
I. of the present papers I stated that this salt retards the 
