MEETINGS OF SOCIETIES. 247 
found to weigh 476lb., containing gold at the rate of 410z, 13dwt. 
16gr. per ton; or in above 476lb. tailings no less than 80z. 17dwt. 
3er. gold. I have brought some of these tailings here. Under 
the microscope there is no gold visible. I thought that ifthe oxide 
of iron were removed, by boiling the tailings in hydrochloric acid, 
and the solution filtered off, the gold might more readily be dis- 
cernible in the boiled-out residue. I tound, however, that this was 
not the case; and that rooogr. of tailings thus boiled in strong 
hydrochloric acid, by which about 20 per cent. were dissolved, gave 
me only o'730gr. of pure gold, while rooogr. of the original tailings 
not boiled out, gave 1°306 gr. of gold, the same as when boiled out 
within nitric acid. The loss of gold by boiling in hydrochloric 
acid was no doubt due to the action of this acid upon manganese 
in the ore, whereby chlorine gas was formed, a ready solvent for 
gold. That the ordinary amalgamating Chilian mill did not extract 
all the gold in this stone I can only attribute to the supposition 
that the oxide of iron has literally coated some of the fine gold, 
thus preventing it from coming in contact with the mercury. For 
such ore, Plattner’s chlorination process, if worked on a large scale, 
ought to be highly successful. I am glad to hear that arrange- 
ments have been made by which the tailings will presently be treated 
at the mine by the chlorination process, whereby the gold is dis- 
solved by an aqueous solution of chlorine gas, and precipitated by 
hydro-su!phuric acid. It would, however, be interesting to see 
whether some or any of the numerous patent gold-extracting 
machineries or appliances would be able to overcome the difficulty, 
and to treat economically and successfully these tailings or the 
original ore. That it would be of great advantage both to a patentee 
and the owners of this mine is evident. While on this subject I 
may be permitted to allude to the want in this colony of a mining 
laboratory, supplied with all the appliances not only for examining 
ores, but for extracting by the most approved methods their 
metalliferous treasures on a large scale. Of course, such an esta- 
blishment would be both extensive and expensive, but while giving 
valuable aid to mining enterprise, it could be made not only 
self-supporting, but remunerative. All depends on its or- 
ganisation and suitability to our wants. I have brought here 
one of the printed circulars issued by the celebrated Govern- 
ment smelting works of Clausthal, Freiberg, and Eisleben, 
in Germany. This circular gives the price-list for extracting 
different metals, such as gold, silver, copper, lead, bismuth, cobalt, 
nickel, arsenic, and zinc from their ores, as well as for treating 
Mint and jewellers’ sweep. From this it will be seen that the 
German Government not only makes use of these establishments 
for home purposes, but actually courts for customers all over the 
world. Such an establishment, with a staff of highly experienced 
officers, would soon become a school wherefrom our future mining 
managers and metallurgists might issue, and our mining industry 
would thus receive the much-wanted scientific basis to work upon 
in developing the great wealth hidden in the bowels of this great 
continent. 2. Preparation of Fine Gold.—The preparation of 
absolutely pure gold, such as is required by assayers, &c., is tedious. 
The gold is dissolved in nitro-muriatic acid, evaporated, largely 
diluted with water to precipitate all silver it may contain, when 
the-gold is precipitated in the filtrate by oxalic or sulphurous acid, 
