The boy was early set to work. When twelve years old he was employed as a "powder-monkey," in making and filling cartridges. After two years, he was passed on to the carpenter's shop where his father worked, and there he became acquainted with tools and the art of working in wood and iron. From the first, the latter seems to have had by far the greatest charms for him. The blacksmiths' shop was close to the carpenters', and Harry seized every opportunity that offered of plying the hammer, the file, and the chisel, in preference to the saw and the plane. Many a cuff did the foreman of carpenters give him for absenting himself from his proper shop and stealing off to the smithy. His propensity was indeed so strong that, at the end of a year, it was thought better, as he was a handy, clever boy, to yield to his earnest desire to be placed in the smithy, and he was removed thither accordingly in his fifteenth year.

His heart being now in his work, he made rapid progress, and soon became an expert smith and metal worker. He displayed his skill especially in forging light ironwork; and a favourite job of his was the making of "Trivets" out of the solid, which only the "dab hands" of the shop could do, but which he threw off with great rapidity in first rate style. These "Trivets" were made out of Spanish iron bolts --rare stuff, which, though exceedingly tough, forged like wax under the hammer. Even at the close of his life, when he had acquired eminent distinction as an inventor, and was a large employer of skilled labour, he looked back with pride to the forging of his early days in Woolwich Arsenal. He used to describe with much gusto, how the old experienced hands, with whom he was a great favourite, would crowd about him when forging his "Trivets," some of which may to this day be in use among Woolwich housewives for supporting the toast-plate before the bright fire against tea time. This was, however, entirely contraband work, done "on the sly," and strictly prohibited by the superintending officer, who used kindly to signal his approach by blowing his nose in a peculiar manner, so that all forbidden jobs might be put out of the way by the time he entered the shop.