Page:Popular Science Monthly Volume 12.djvu/465

From Wikisource
Jump to navigation Jump to search
This page has been validated.
THE GROWTH OF THE STEAM-ENGINE.
449

82. About 1785 John Fitch and James Rumsey, two ingenious American mechanics, were engaged in experiments having in view the application of steam to navigation.

83. Rumsey's experiments began in 1774, and in 1786 he succeeded in driving a boat at the rate of four miles an hour against the current of the Potomac, at Shepardstown, Maryland.

Rumsey employed his engine to drive a great pump, which forced a stream of water aft, thus propelling the boat forward.

This same method has been recently tried again by the British Admiralty in the Water-witch, a gunboat of moderate size, using a centrifugal pump to set in motion the propelling stream, and with some other modifications which are decided improvements upon Rumsey's rude arrangements, but which have not done much more than did his toward the introduction of "hydraulic propulsion," as it is now called.

Rumsey died of apoplexy while explaining some of his schemes before a London society a short time later.

84. John Fitch was an unfortunate and eccentric, but very ingenious, Connecticut mechanic.

After roaming about until forty years of age, he finally settled on the banks of the Delaware, where he built his first steamboat.

In 1788 he obtained a patent for the application of steam to navigation.

His boat is shown in Fig. 46; it was sixty feet long and twenty

Fig.—46 John Fitch, 1788.

feet wide. The propelling apparatus was a system of paddles, which were suspended by the upper ends of their shafts, and moved by a series of cranks, one to each, taking hold at the middle, and giving them almost exactly the motion which is imparted to his paddle by the Indian in his canoe.