MONORAIL, a single-rail type of railway designed for economy of construction, in creased speed and for mountainous regions. The first idea of a single-rail railway dates back to 100 years ago, and many such are now being used in various parts of the world.
The first car run on a single rail, the inven tion of M. Charles Lartigue, has been in prac tical operation for may years in Djiboniti, a French-African post. The car is kept vertical by its attachment to a laterally placed horse, which balances the car as a hansom is balanced by attaching the horse in front. The develop ment of this primitive idea attracted the genius of all great civilized countries, and aided by government patronage, individual effort and fortunes, made great progress.
An early type of monorail was one where all the different resistances to a swiftly moving car or train, except the atmospheric resistance, was concentrated in tite vertical of the centre of gravity of the car or train, being par tially concentrated by centrifugal force, and those resistances which were not concentrated at the centre are nearly compensated for by friction removing devices. When the said body is at rest, or slowly moving, the unbalanced forces, only, are mechanically concentrated with a minimum friction, and the stability is posi tively and absolutely preserved without jarring movement. The downward vertical force con sists of the weight of cars, trucks and load. This weight is delivered to, and directly sus tained by, two centrally disposed bearing rails laid with precision as to alignment and surface, and closely gauged to each other, so as to con stitute practically a single support, while the vertical integrity or stability of the weight thus delivered to a central point is conserved when necessary by upward forces acting through the medium of dependent tension members, fitted with frictionless wheels hearing against in verted girders or rails; when moving at speed, stataty is almost entirely preserved naturally and automatically, and only slight strain is on the dependent tension members. The magni
tude of the downward forces is a matter sim ply of weight of cars; the upward forces are a matter of mechanical moments or leverages; the upward forces may amount to 10 per cent of the downward forces for usual cases. The downward force is delivered through the me dium of the main central wheel, bearing on the two central rails as on a single rail. The side clutch wheels, that bear against the inverted girders or rails, guide, clutch and secure the car truck to its normal plane or path, forcing the truck to follow precisely any assigned in clination ; for example, around curves. The central bearing rails and the inverted side clutch rails being laid with precision as to line, grade and inclination, the lateral and top-heavy swaying and recurrent oscillation now observ perienced railroad men as Austin Corbin. Sev eral short test roads were built and operated. The Tunis plan, here illustrated, is a modifica tion of Boynton's. As will be seen, the single rail is laid on the ground like the rails of steam roads and trolley lines. Over the single rail able in locomotives in motion can never obtain; nor can the truck derail, as it is clutched to the track The propulsion of cars is effected 'by electric motors, two or four motors to each truck, the number of motors being dependent upon the starting pull, acceleration and speed required.
William B. Mack's design, shown here, ap pears to have been awarded more consideration among engineers than any of the many similar plans patented. As far back as 1872 a charter was granted in the State of New York for the building of a hanging railroad which had the general mechanical principles of the hanging roads more recently exploited in Germany, France and Russia, but the Cook system, shown here, appeared to be the only serious effort made to date at hanging cars on the side of the structure in place of underneath.