Besides attending to the underground arrangements, the improved transit of the coals above ground from the pit-head to the shipping-place demanded an increasing share of Stephenson's attention. Every day's experience convinced him that the locomotive constructed by him after his patent of the year 1815 was far from perfect, though he continued to entertain confident hopes of its complete eventual success. He even went so far as to say that the locomotive would yet supersede every other traction-power for drawing heavy loads. It is true, many persons continued to regard his traveling engine as little better than a dangerous curiosity; and some, shaking their heads, predicted for it "a terrible blow-up some day." Nevertheless, it was daily performing its work with regularity, dragging the coal-wagons between the colliery and the staiths, and saving the labor of many men and horses. There was not, however, so marked a saving in the expense of haulage as to induce the colliery masters to adopt locomotive power generally as a substitute for horses. How it could be improved, and rendered more efficient as well as economical, was constantly present to Stephenson's mind. He was fully conscious of the imperfections both in the road and the engine, and gave himself no rest until he had brought the efficiency of both up to a higher point. Thus he worked his way inch by inch, slowly but surely, and every step gained was made good as a basis for farther improvements. At an early period of his labors, or about the time when he had completed his second locomotive, he began to direct his particular attention to the state of the Road, perceiving that the extended use of the locomotive must necessarily depend in a great measure upon the perfection, solidity, continuity, and smoothness of the way along which the engine traveled. Even at that early period he was in the habit of regarding the road and the locomotive as one machine, speaking of the Rail and the Wheel as "Man and Wife." All railways were at that time laid in a careless and loose manner, and great inequalities of level were allowed to occur without much attention being paid to repairs. The consequence was a great loss of power, as well as much wear and tear of the machinery, by the frequent jolts and blows of the wheels against the rails. Stephenson's first object, therefore, was to remove the inequalities produced by the imperfect junction between rail and rail.