Take 1 ounce of ammoniac and 1 ounce of common salt, an equal quantity of calcined tartar, and 3 ounces of antimony. Pound this well together and sift. Put this in a piece of linen, and enclose it well around with fullers' earth about an inch thick, let it dry, then put it in one crucible, covered by another crucible over a slow fire to get hot by slow degrees. Keep up the fire until the content of the crucible gets red-hot and melts. Then let it cool gradually, and when cold pound the mixture. When you wish to solder anything put the two pieces you want to join together on a table close to one another. Make a crust of fullers' earth, so that, passing under the joint and holding to each piece it shall be open at the top. Then threw some of the powder between and over the joint. Dissolve some borax in some hot wine, and with a feather dip in the solution and rub the powder at the place of the joint. It will immediately boil up. As soon as the boiling stops the consolidation is made. The calcined tartar is made by placing crude tartar in a covered crucible and raising it to a low red heat. Allow it to cool gradually. Joseph M. Stabel. Rochester, N. Y.
For flux use 1 part metallic sodium to 50 or 60 parts of mercury. These combine if well shaken in a bottle. For solder use a weak solution of copper sulphate, about 1 ounce sulphate to 1 quart of water; precipitate the copper by rods of zinc, wash the precipitate two or three times with hot water, drain off the water and add 6 or 7 ounces of mercury for every 3 ounces of precipitate. A trifle of sulphuric acid will assist in the combining of the matter. The combination will form a paste which sets very hard in a few hours. A. L. Monrad.
New Haven, Conn.
I have seen a number of different formulas for soldering acids and have had occasion to try several of them with more or less satisfaction. Among all the different ones which I have tried, I know of but one, however, that actually can be said to fill all requirements.
The acid is composed of: Solution chloride zinc, 1 ounce; glycerine, 1 ounce. alcohol, 7 ounces.
As far as the solder itself is concerned, one can, of course, make compositions of tin and lead in almost any proportions to fill the requirements in general. The melting point of these different compositions will vary greatly, however, according to the proportions of above metals in same, and, of course, this is an important factor in many instances, especially when wanting to solder metals which have a low melting temperature, in which case the solder ought to be a composition which Itself will melt at a very low temperature. If bismuth is added to the composition the melting temperature will almost invariably be lowered. I have on hand a fairly complete table of compositions for solder, giving their respective melting temperatures and the metals for which they are best adapted: