The Mechanical Handling and Storing of Material

338 THE MECHANICAL HANDLING OF MATERIAL generally on a single rail and supporting in a suspended position a receptacle to carry the load. The bogie or trolley is fitted with and propelled by an electro-motor which collects its current by a small trolley pole from the single, double, or triple overhead conductors, arranged alongside and supported on the track structure. There is no limit to the distance of travel, and the telpher may either be a man- telpher, that is, accompanied by an attendant, who from his cab starts, stops, lowers, or ■dumps his load and returns for a further one ; or it may be so arranged that all movements are automatic, so that the telpher with its load, when released at the loading ■terminal, travels automatically to a predetermined position, dumps its load and returns empty to the starting point for a new load. Some of the man-telphers are fitted with one or two electric winches to pick or lower loads at any point on the line, and in order to save labour some are so constructed that the attendant can lower himself or rise with the load to detach or attach it on the ground. Such appliances are made by the Link Belt Company. Automatic telphers have been perfected to an astonishing degree. They are provided with a perfect automatic block system, the passing telpher establishing its own electric connection, so that no second carrier can enter the line within a predetermined distance of that in front, and if one is stopped for some cause or another all the succeeding ones will stop at the same distances apart. To give a full description of the intricate electrical fittings would occupy more space than is available.1 Telphers for large and bulky loads are fitted with a trailer, or double telphers are used, either direct connected or geared; the latter is generally the case where an excessive gradient has to be negotiated. The speed of travel varies from 4 to a maximum of 20 miles per hour, according to the nature of the load, the capacity required, and the gradient of the track. The track may lead over buildings and across rivers. It is sometimes bracketed to the sides of buildings, at others supported on the open land on A-brackets. The load can be switched on to branch lines over track switches, which the telpher man himself operates from his cab. The telpher man can also reverse his machine at will, open and close doors, run the entire length of the storehouse or shop, and pick up loads without any previous preparation In and out handling from the works is equally well performed by the same telpher, and there is no limit as to distance. Mono-rail telphers have been more particularly applied to gas and electricity undertakings for the purpose of handling the large quantities of coal and coke which have to be continuously dealt with in such works, and are employed in nearly all the largest gas and electricity works in this country, also in some on the Continent. These appliances seem to be particularly applicable where the duty is heavy and continuous, and where the route to be traversed is anything but in a straight line, and also where branch runs have to be made off the main road. These telpher machines are usually designed to travel upon a single rail, which is generally bolted to the top flange of rolled steel girders of suitable depth and flange width—according to the span between the available supports. There may be as many curves and branch turnouts as are necessary—the design of the machines being such that any reasonable curve can be negotiated with ease and safety. They have been built for dealing with loads up to 4 tons, but there is no reason why heavier loads should not be dealt with if the necessity arises. 1 Automatic telpherage is fully dealt with by A. J. Wallis-Tayler in his book, “Aerial or Wire Rope-Ways ” ; also by Dr P. Stephan in “ Die Drahtseilbahnen,1’ an English translation of which is under preparation.