necessary to file and smooth the surfaces again. The constant use of muriatic acid on the copper soon wears it away and makes it unfit for use. Rosin is easily carried and applied and is by far the best to use in regular work.
POINTS TO REMEMBER IN THE CARE OF THE SOLDERING IRON.--
First, proper tinning is absolutely necessary for rapid and good work.
Second, do not allow the iron to heat red hot.
Third, keep the point of the iron properly shaped.
Fourth, use the same flux in tinning as is to be used in soldering.
Fifth, when filing iron, file as little as possible.
Sixth, keep in use two irons of the same size.
A flux is used to clean the surfaces of joints and seams to be soldered, also to keep them from oxidizing and to help the metals to fuse.
The following list gives the names of various fluxes in common use, how they are applied, and on what material they are most commonly use