Railway enterprise was not checked by the great cost of the undertakings, nor by the miscalculations of the engineers, who, in the first instance, frequently greatly under-estimated the expenditure requisite for the cuttings, embankments and tunnels, which were thought necessary to attain as perfect a level as possible. The original estimate for the Liverpool and Manchester Railway was £300,000, but the amount expended on the works at the time of opening was nearly £800,000. The original estimate of the London and Birmingham Railway, including the purchase of land, and the locomotives and carriages, was £2,500,000, whilst the actual cost amounted to £5,600,000, the cost of the works and stations being about £38,000 per mile. The Grand Junction Railway, from Birmingham to Liverpool, was more economically constructed, because the difficulties to be surmounted were not so great, and less attention was paid to maintain a level line. It was estimated to cost, including all charges, £13,300 per mile, though the actual cost was £23,200. The plan adopted for laying down and fixing the rails on all the railways in England, with the exception of the Great Western, is nearly similar to that on which the original coal-pit railways were constructed. Pieces of timber, called "sleepers," are laid at short distances across the road, and on to these sleepers are fixed cast iron "chairs," into which the rails are fastened by wedges, the sleepers being afterwards covered with gravel or other similar material, called "ballast," to make the timbers lie solidly, and to keep the road dry. The railway system of Great Britain was commenced without sufficient attention to the determination of the best width apart of the rails. In forming the Liverpool and Manchester Railway, the guage of the railways in the collieries was adopted, and the width between the rails was made 4 feet 8½ inches. The same width of rails was adopted on the London and Birmingham and Grand Junction Railways; and as uniformity of guage was essential to enable the engines and carriages on one line to travel on another, the other railways connected with the grand trunk line were made of the same width of guage. Mr. Brunel, the engineer of the Great Western Railway, departed from that uniformity, and laid down the rails 7 feet apart. The increased width of guage possesses many advantages, of which greater steadiness of motion and greater attainable speed, without risk, are the most important; but, at the same time, the additional space incurs a greater expense in laying out the line. As branches from the Great Western Railway spread into the districts where the narrow guage railways had been laid down, much inconvenience has arisen from the break of guage, as it occasions the necessity for a change of carriages. On some railways, to avoid this inconvenience, narrow and broad guage rails have been laid down on the same line.