Dolter Electric Traction
of 62 New Broad Street, London
1901 The company was registered on 21 May, to acquire certain British and Colonial patents relating to electric traction. [1]
1907 Installed at Torquay Tramways Co
1908 Company in liquidation.[2]
The Dolter is claimed be the lease obtrusive of all electric systems. the centre of the track are studs or contact boxes, hardly noticeable when laid with wood-paving, at intervals of 15 feet. Underneath are the studs themselves, in shape and size like jam-bottles, and, of course, in proximity, the cable along which the current runs.
The mechanism is simple, consisting of a lever with a carbon contact, which is brought into sharp connection with fixed carbon on the side of each box by the action of a very powerful magnetised skate, or fiat piece of steel, affixed to the bottom of the car, which presses upon the top of each stud encountered during the journey. soon as the skate reaches the top of a stud the lever is set in motion, and the car obtains the necessary electric energy for the continuation of its rim. The skate is not formed of one rigid piece from end to end, but by several jointed sections, thereby preventing excessive wear. It also lends itself to the unevenness of road, turning corners or travelling round curves easily, without in the slightest degree affecting its efficiency in obtaining the current. The size of the studs is about 9in. by -lin. by Tin. deep. Two small holes are sunk in the top of each stud or contact box, so that at any time it may be taken out means of a key and easily replaced ; by this means, the cable can be changed or renewed as circumstances require. As a matter of precaution, the skate under the car is followed by a safety skate, which absolutely precludes the possibility of shock destroying any electrical power left the boxes. The stud is only alive at the moment the car passes over.
The system is in working order on the Chemin de fer, Bois de Boulogne, Paris, and on the routes to the well-known racecourses at Longchamps and St. Cloud, and is the only system adopted by the French Board Trade. One of the most formidable objections the conduit and other ground-level systems has been that of flooding alter continued heavy rainfall, but in Paris, at certain times of the year, hundreds of yards of the track are under water, and yet the system works perfectly.[3]