Electrical Forging.

A large audience gathered in the Jefferson Physical Laboratory last evening to hear Mr. George Burton of Boston explain his method of electrical forging. The scheme of heating metals by electricity and thus forging them has hitherto been found impracticable, and Mr. Burton is the first man to discover methods for making such operations not only practicable but also successful from a financial point of view. He briefly explained note-worthy features of his method, and then gave some sixty stereopticon views to illustrate both the machines and the finished product of the process. He had also abundant samples of the work in all metals on exhibition.

Mr. Burton's invention makes a revolution in the forging business. Formerly metals were heated by fire and then pounded into the desired shapes. The one primary improvement effected by the electrical method is that the metals have to be heated but once. An electric current that is held under absolute control is passed through the metal, and by means of delicate mechanism, just the same degree of heat can be maintained in the metal for an indefinite length of time. Under the old method, the metal would soon become cold and have again and again to be heated, so that a great amount of time is saved by this new system.

The absolute control of the current is therefore the first essential, and Mr. Burton has found that by making the rheostats not out of wire but out of liquids that more perfect control is obtained. Mr. Burton has also discovered that when several metals are heated by the same currents, the softer are not fused more quickly than the harder; in other words, each metal calls for its appropriate amount of the current. Thus he is enabled to heat iron, copper, and brass all by one current.

The second great improvement of his method is that, since the metal is heated uniformly and continuously, it can be forged into shape by machines with perfect accuracy. It is no longer necessary that a man should pound only where the heat remains in the metal, now by one turn of a machine, the metal is twisted into the desired shape, and the finished product has been produced.

In time cost, and quality of workmanship a+++ke the new method asserts its superiority. Mr. Burton has a large establishment on Oliver street, in Boston, and there his inventions can be seen in practical form.