A History of the Growth of the Steam-Engine

by Robert Henry Thurston

Hedley, who had known of the success met with in the experiments of Trevithick with smooth wheels hauling loads of considerable weight, in Cornwall, was confident that equal success might be expected in the north-country, and built a carriage to be moved by men stationed at four handles, by which its wheels were turned.

This carriage was loaded with heavy masses of iron, and attached to trains of coal-wagons on the railway. By repeated experiment, varying the weight of the traction-carriage and the load hauled, Hedley ascertained the proportion of the weight required for adhesion to that of the loads drawn. It was thus conclusively proven that the weight of his proposed locomotive-engine would be sufficient to give the pulling-power necessary for the propulsion of the coal-trains which it was to haul.

When the wheels slipped in consequence of the presence of grease, frost, or moisture on the rail, Hedley proposed to sprinkle ashes on the track, as sand is now distributed from the sand-box of the modern engine. This was in October, 1812.

Hedley now went to work building an engine with smooth wheels, and patented his design March 13, 1813, a month after he had put his engine at work. The locomotive had a cast-iron boiler, and a single steam-cylinder 6 inches in diameter, with a small fly-wheel. This engine had too small a boiler, and he soon after built a larger engine, with a return-flue boiler made of wrought-iron. This hauled 8 loaded coal-wagons 5 miles an hour at first, and a little later 10, doing the work of 10 horses. The steam-pressure was carried at about 50 pounds, and the exhaust, led into the chimney, where the pipe was turned upward, thus secured a blast of considerable intensity in its small chimney. Hedley also contracted the opening of the exhaust-pipe to intensify the blast, and was subjected to some annoyance by proprietors of lands along his railway, who were irritated by the burning of their grass and hedges, which were set on fire by the sparks thrown out of the chimney of the locomotive. The cost of Hedley’s experiment was defrayed by Mr. Blackett.

Subsequently, Hedley mounted his engine on eight wheels, the four-wheeled engines having been frequently stopped by breaking the light rails then in use. Hedley’s engines continued in use at the Wylam collieries many years. The second engine was removed in 1862, and is now preserved at the South Kensington Museum, London.

George Stephenson.

[George Stephenson], to whom is generally accorded the honor of having first made the locomotive-engine a success, built his first engine at Killingworth, England, in 1814.

At this time Stephenson was by no means alone in the field, for the idea of applying the steam-engine to driving carriages on common roads and on railroads was beginning, as has been seen, to attract considerable attention. Stephenson, however, combined, in a very fortunate degree, the advantages of great natural inventive talent and an excellent mechanical training, reminding one strongly of James Watt. Indeed, Stephenson’s portrait bears some resemblance to [that] of the earlier great inventor.