7 a 
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gold formed on the plate, which increased :0082 g. in weight in 
>) 
026 A. LIVERSIDGE. 
nine days only. 
Eaperiment 29, with galena.—The cleavage planes became gilt 
almost immediately, 7.e., in a minute or so; without the gold 
nucleus the gilding takes an hour or two. As the deposit of gold 
thickens it loses its brilliancy. After a fifteen days action the 
gold plate had become dull from the gold deposited upon it; 
increase ‘0049 in fifty-nine days. 
Experiment 30, with galena, Broken Hill, N.S.W.—The gold 
deposited on the galena was black, but brown in places, with a few 
rectangular specks of bright gold ; some lead sulphate had also 
formed. The gold on the gold plate was of a copper colour. The 
foil increased ‘0281 g. in weight. 
Experiment 31, with zinc blende.—Decolourised several charges. 
The foil was unchanged. On dissolving the blende, much dull 
spongy gold was left mixed with a few bright crystallised points 
seated on the gold, one St. Andrew’s cross was very distinct, also 
some with six rays, but all microscopic. 
Experiment 32, with zinc blende.—Increase in weight of plate 
was ‘0086 g. Mixed with the dull vermicular gold on the blende 
were scattered hexagonal crystals of bright gold. 
By vermicular or vermiform gold is meant a more or less close 
net work of worm-like rounded and irregular threads of gold, 
which eventually coalesce in the thicker deposits and form a 
mamumillated surface. 
Heaperiment 33, with graphitic casing from an auriferous vein-— 
It decolourised two ounces of the solution in five days and suc- 
cessive quantities afterwards. The surface of the graphitic 
_ casing became completely coated with a very thick deposit of dark 
coloured mammillary gold, but in a few places were some minute 
crystals of bright gold showing up most brilliantly; they appeared 
tobe hexagonal plates. The gold foil did not show any increase 
in weight. 
In this instance as well as in that of the coal, graphite and 
charcoal, the gold appeared to be thrown down entirely upon the 
