Uncle Fritz was so well pleased at their eagerness that he brought out for them some of the old books, and some of the new. In especial he bade them all read Smiles's "Life of Stephenson" before they came to him again. For to George Stephenson, as they soon learned, more than to any one man, the world owes the step forward which it made when locomotives were generally used on railroads. Since that time the improvements in both have gone on together. Before they met again, at Uncle Fritz's suggestion, Fergus and Hester prepared this sketch of the details of Stephenson's earlier invention, purposely that Uncle Fritz might use it when these papers should be printed together. GEORGE STEPHENSON. An efficient and economical working locomotive engine still remained to be invented, and to accomplish this object Stephenson now applied himself. Profiting by what his predecessors had done,--warned by their failures and encouraged by their partial successes,--he began his labors. There was still wanting the man who should accomplish for the locomotive what James Watt had done for the steam-engine, and combine in a complete form the best points in the separate plans of others, embodying with them such original inventions and adaptations of his own, as to entitle him to the merit of inventing the working locomotive, as James Watt is to be regarded as the inventor of the working condensing-engine. This was the great work upon which George Stephenson now entered, though probably without any adequate idea of the ultimate importance of his work to society and civilization. He proceeded to bring the subject of constructing a "Travelling Engine," as he denominated the locomotive, under the notice of the lessees of the Killingworth Colliery,[16] in the year 1813. Lord Ravensworth, the principal partner, had already formed a very favorable opinion of the new colliery engine-wright from the improvements which he had effected in the colliery engines, both above and below ground; and after considering the matter, and hearing Stephenson's explanations, he authorized him to proceed with the construction of a locomotive, though his lordship was by some called a fool for advancing money for such a purpose. "The first locomotive that I made," said Stephenson, many years after, when speaking of his early career at a public meeting in Newcastle, "was at Killingworth Colliery, and with Lord Ravensworth's money. Yes, Lord Ravensworth and partners were the first to intrust me, thirty-two years since, with money to make a locomotive engine. I said to my friends, there was no limit to the speed of such an engine, if the works could be made to stand."