Jacob Perkins, an American inventor, born in Newburyport, Mass., July 9, 1766, died in London, July 30, 1849. He was apprenticed to a goldsmith, and invented a new method of plating shoe buckles. When he was about 21 years of age he was employed by the commonwealth of Massachusetts to make dies for copper coinage. Soon afterward he invented a machine for cutting and heading nails at one operation, but through the mismanagement of his partners he was involved in great pecuniary distress. In bank-note engraving he made most important improvements, substituting steel for copper plates. (See Engraving.) About 1814 he went to Philadelphia and became associated with the firm of Murray, Draper, and Fairman, bank-note engravers. In 1818 he went to England, accompanied by Mr. Fairman and a number of workmen, and obtained a contract for supplying the bank of Ireland with plates, and in partnership with Mr. Heath carried on his business in London for a number of years. He also constructed a gun in which steam, generated at an enormous pressure, was used as the propelling power instead of gunpowder, and instituted experiments which demonstrated the feasibility of his plan, though it has been generally condemned as inapplicable to modern warfare.

Balls passed through 11 planks of the hardest deal, each an inch thick, placed some distance apart, and with a pressure of only 65 atmospheres penetrated an iron plate a quarter of an inch thick. He screwed to a gun barrel a tube filled with balls, which falling into the barrel by their own weight were discharged at the rate of nearly 1,000 a minute. The expense of working such a gun was calculated at about 1/200 part of the cost of the powder required to discharge an equal number of balls by the usual method. Mr. Perkins also invented an instrument called the bathometer, to measure the depth of water, and the pleometer, to mark with precision the speed at which a vessel moves through the water; and he was the first to demonstrate that water is compressible.