Round iron spikes, as in Figs. 323 and 324, and round wooden trenails, as in Fig. 325, are both used for fastening cast-iron chairs to the sleepers. The spikes are made with a slightly taper neck, of size rather less than the hole in the chair, to avoid risk of breaking the casting when driving the spike down. Trenails are made out of well-seasoned hard wood, and are compressed by machinery. When driven into the sleeper, they expand by exposure to the atmosphere, and hold the chair very securely in position; but being only wood and of very small scantling, they are subject to early decay. The head, which is the only part in sight, may be perfectly sound, while the part between the chair-seat and top of sleeper may be quite rotten and useless. It would be very risky to depend upon trenails alone; one spike at least should be used to every chair. In some cases an extra large trenail is used with an augur-hole down the centre, through which either an iron spike is driven or a bolt is passed and screwed into a crab-nut on the under side of the sleeper. This arrangement will work well for a time, but there will be a great deal of play in the spike or bolt when the trenail becomes much decayed. The spikes represented in Figs. 326, 327, and 328, are much used with flange rails. They are square in section, and finished with either blunt or sharp points, as shown. The top of spike is made with a doghead and side-lugs to facilitate the easing or withdrawal when necessary for renewals of sleepers, or alterations in line. By inserting the curved double claw end of a platelayers’ crowbar, the spike can be raised without injuring the sleeper; but if it is required to be driven into the same sleeper again, a new hole must be bored, as the old hole will be too slack to be of any service. Augur-holes must be bored in the sleepers for the above spikes. For new roads, these holes can be bored by machinery when cutting the grooves for rail-seats; but when carrying out alterations or repairs, a large number of spike-holes must be bored by hand-augurs, an operation both slow and laborious. With the hand-boring there is the danger that the hole may not be made deep enough, owing to the workman’s 223 endeavour to avoid damaging the point of his augur by forcing it entirely through the sleeper, and bringing it in contact with a stone. Augur-holes bored wide to gauge will remain out of gauge, and although the spike may be driven down firm in its position, a space will be left for play between the rail-flange and spike.