PHYSICAL ang LITERARY. 311 
_ WueEw a plate of copper is put into a folu- 
tion of filver diluted, the furface of the cop- 
per is immediately covered, as it were, with 
a coat of filver; this becomes gradually 
thicker, and appears tufted, {pungy and loofe: 
upon fhaking the plate, large pieces of this 
cruft fall off, which either rife to the top, 
or fwim, about in the liquor for a while, till 
difcharging many bubbles of air, they. grow 
heavier, and fall down in form of a white 
powder.; the filver being in this manner fe- 
parated. from the liquor, then wafhed and 
dried, is. nearly of the fame weight with 
the filver diflolved ; and; when melted, runs 
into a lump of pure malleable fi lver, without 
any confiderable lofs. | 
Tr an alcaline liquor, : as _fpir. fal. ammoni- 
aci, or ol. tartari p. d. is dropt into a folution 
of filver, it excites a ftrong effervefcence, 
which will be renewed when more of the al- 
caline liquor is dropt in at intervals, until the 
acid is fatiated ; and there appears a white, 
bulky and frothy matter, which gradually 
fubfides: all being thrown into a cap of 
brown paper, fitted to a funnel, and warm 
water poured in, the frothy matter diminifhes 
peiecaeits in bulk; and there is left a 
powder 
ig ee ee ee a oe 
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