After a year or two in his father's locomotive factory, Robert spent two or three years in charge of the machinery of a mining company in Columbia, and returned to England at the close of 1827, to find the great question, "Whether locomotives can be successfully and profitably applied to passenger traffic?" hotly agitated, his father, almost alone, taking the side of the travelling, against that of the fixed engines, and insisting that the wheel and the rail were clearly and closely part of one system. The success of the Darlington line induced the Liverpool merchants to project a line between that town and Manchester; and George Stephenson was almost unanimously chosen engineer, though it was still undetermined whether the new line should be worked by steam or horse power. But, apart from that question, a great, and, as it appeared to most of the engineers of the time, an insurmountable difficulty existed in the quagmire of Chat Moss,--an enormous mass of watery pulp, which rose in height in wet, and sank in dry weather like a sponge, and over whose treacherous depths it was pronounced impossible to form a firm road. It was perfect madness to think of such a thing, said the engineers, and none of them would support Stephenson's scheme; but he resolved to see what could be done. Truck-load after truck-load of stuff was emptied into the moss, and still the insatiable bog kept gaping as though it had not had half a feed. The directors, alarmed, would have abandoned the project, had they not been so deeply involved that they were obliged to let Stephenson continue. But he never doubted himself--not for a moment. He only pushed on the works more vigorously; and, before six months were over, the directors found themselves whirling along over the very bog they expected all their capital was to be fruitlessly sunk to the bottom of. Still, no decision had been come to as to whether locomotive or fixed engines were to be adopted; and the Stephensons were still battling bravely in favour of the locomotive against a host of opponents. Robert did his father good service by the able and pithy pamphlets which he wrote on the subject; and at length their perseverance was rewarded by the directors consenting to employ a locomotive, if they could get one that would run at the rate of ten miles an hour, and not weigh more than six tons, including tender; and offering a reward of L500 for the best engine fulfilling these conditions. George Stephenson and his son set to work immediately, and the product of their united skill and ingenuity was the celebrated _Rocket_, which carried off the prize, and attained a speed of twenty-nine miles on the opening day. The practicability and success of the locomotive was now beyond a doubt; from that day forward public opinion began to turn. Of course, for many a long year afterwards there were not wanting numbers of bigoted men of the old school who cried down