Conception which unravels and illuminates the tangle of silver and platinum. The silver might be an additional signal signifying, "Fast train approaching." The block system--Position of signals--Interlocking the signals--Locking gear--Points--Points and signals in combination--Working the block into which this motion is apparently destroyed, without producing evident impression, _our_ surprise is changed into delight and satisfaction, gazing at the abruptness of the iron.