The difficulty was overcome by providing at each passing loop an instrument containing a number of staffs locked in a frame by electrical means. The driver of a train entering the single-line section glances at the indicator. When the driver reaches the end of the section, he places the staff in the instrument at the passing loop. This action unlocks the frames at both ends of the section, ready for further use. It will be noted that only one staff can be used on the section at one time.
Telegraphic communication exists between all stations and signal boxes.
Although on a small scale, the line has engine sheds, constructing and repairing shops, crossings, points and signals in the same way as the standard gauge railways. There are many quaint and unusual sights on this railway, such as the old-type signals, now derelict, but still standing here and there along the line. There are no platforms at the stations, and the carriage doors are always locked, a necessary precaution not only against possible accidents to passengers but also against damage to rolling-stock, the clearance between the side of the train and the rock along the line and in tunnels being less than the width of a carriage door. An interesting, sight is a train of trucks loaded with slates, sometimes as many as fifty or sixty, travelling down the line without an engine. These trains are controlled by hand brakes on trucks at intervals along the train, which are operated by brakemen who run along the tops of the trucks to put them on or take them off according to the gradient.