Although Stephenson had, with every step made towards its increased utility, become more and more identified with the success of the locomotive engine, he did not allow his enthusiasm to carry him away into costly mistakes. He carefully drew the line between the cases in which the locomotive could be usefully employed, and those in which stationary engines were calculated to be more economical. This led him, as in the instance of the Hetton Railway, to execute lines through and over rough countries, where gradients within the powers of the locomotive engine of that day could not be secured, employing in their stead stationary engines where locomotives were not practicable. In the present case, this course was adopted by him most successfully. On the original Hetton line, there were five self-acting inclines,—the full waggons drawing the empty ones up,—and two inclines worked by fixed reciprocating engines of sixty horse power each. The locomotive travelling engine, or “the iron horse,” as the people of the neighbourhood then styled it, did the rest. On the day of the opening of the Hetton Railway, the 18th November, 1822, crowds of spectators assembled from all parts to witness the first operations of this ingenious and powerful machinery, which was entirely successful. On that day five of Stephenson’s locomotives were at work upon the railway, under the direction of his brother Robert; and the first shipment of coal was then made by the Hetton Company, at their new staiths on the Wear. The speed at which the locomotives travelled was about 4 miles an hour, and each engine dragged after it a train of 17 waggons, weighing about 64 tons.