The engines that Mr. Blackett had built, using Trevethick’s model as a basis, were working daily near the Killingworth Colliery, and Stephenson frequently went over to see them. He studied Mr. Blackett’s latest locomotive, nicknamed “Black Billy,” with the greatest care, and then told his friend Jonathan Foster that he was convinced that he could build a better engine than Trevethick’s, one that would work more effectively and cheaply and draw a train of cars more steadily. He also had the advantage of seeing other primitive locomotives that were being tried at different places near Newcastle. One of these, known as Blenkinsop’s Leeds engine, ran on a tramway, and would draw sixteen wagons with a weight of seventy tons at the rate of about three miles an hour. But the Blenkinsop engine was found to be very unsteady, and tore up the tram-rails, and when its boiler blew up the owner decided that the engine was not worth the cost of repair. Stephenson, however, drew some useful points from it, as well as from each of the other models he saw, and proposed to himself to follow Watt’s example in constructing his steam-engine, namely, to combine the plans and discoveries of other inventors in a machine of his own, and so achieve a more complete success. Stephenson was now very well regarded at the colliery for the improvements he had made there. He brought the matter of building a new “Traveling Engine,” as he called it, to the attention of the lessees of the mine in 1813. Lord Ravensworth, the principal partner, formed a favorable opinion of Stephenson’s plans, and agreed to supply him with the funds necessary to build a locomotive. With his support Stephenson went to work to choose his tools and workmen. He had to devise and make many of the tools he needed, and to train his men specially for this business. He built his first engine in the workshops at the West Moor Mine. It followed to some extent the model of Blenkinsop’s engine. It had a cylindrical boiler, eight feet long and thirty-four inches in diameter, with an internal flue tube passing through it. The engine had two vertical cylinders and worked the propelling gear with cross-heads and connecting-rods. The power of the two cylinders was carried by means of spur-wheels, which continued the motive power to the wheels that supported the engine on the rails. The engine was simply mounted on a wooden frame that was supported on four wheels. These wheels were smooth, as Stephenson was convinced that smooth wheels would run properly on an edge-rail. This engine, christened the “Blutcher,” and taking about ten months to build, was tried on the Killingworth Railway on July 25, 1814. It proved to be the most successful working engine that had yet been built, and would pull eight loaded wagons of about thirty tons’ weight up a slight grade at the rate of four miles an hour. For some time it was used daily at the colliery.