ELECTRO METALLURGY.

Dissolve an ounce of sulphate of copper in a half pint of water; add a

few drops of sulphuric acid; connect with the zinc pole of the battery

the object to be coppered. To the wire connected with the carbon

attach a small plate of copper. Hang the object and the copper plate

in the solution a short distance apart. A deposit of copper will be

quickly formed.

Scientific American Supplement, No. 794, March 21, 1891 · 第 53 / 71 题