Phosphor Bronze, a compound formed by the addition of a small percentage of phosphorus to gun metal (bronze containing from 90 to 91 parts of copper to 9 or 10 of tin), possessing remarkable properties, in some respects like those conferred upon iron by carbon when made into steel. Experiments in making phosphor bronze have been conducted by the Messrs. Montefiore-Levi and Kunzel, near Liege, Belgium. The addition of a little over one half per cent, of phosphorus gives the metal greater fluidity in casting, and greatly increases its strength and elasticity. In trials recently made at the royal academy of industry in Berlin, a bar of phosphor bronze under a constant strain of 10 tons to the square inch resisted 408,230 pulls, while a bar of ordinary bronze broke before the strain of 10 tons to the square inch had been applied. A bar of phosphor bronze under 10 tons strain resisted 862,980 bends, while the best gun metal broke after 102,650 bends. In Austria the following comparative results have been obtained:

MATERIALS.

Resistance in lbs. per sq. in.

Point of elasticity.

Elongation per cent.

Phosphor bronze..........

81,795

54.915

1.6

Krupp's cast steel, as used for guns....

72,258

14,450

11.0

Ordnance bronze..........

31,792

5,562

15.0

"When immersed in sea water the best English copper sheets lost during six months over three per cent., while phosphor bronze sheets lost but little more than one per cent. It has been found to be superior to iron or ordinary bronze for the tuyeres of blast furnaces, and the manufacture of phosphor bronze has been commenced in this country.