A silver solder for soldering copper is composed of 5 parts of copper, 3 parts of zinc, and 2 parts of silver. Melt the copper first, then add the silver, and lastly the zinc; directly the zinc is immersed, rapidly stir the alloy so as to render its composition equal throughout, and then east it in a small ingot mould. The ingot is then rolled down to form a small sheet equal to about No. 18 B.W.G. gauge in thickness, and from this narrow strips are cut as required. Ordinary solder may be converted into fine solder by me ting and then' adding the silver in the proportion given above.