lexible girders nearly parallel to
each other, so that when necessary the load to be transported may be
suspended from or borne by both tram wires jointly or simultaneously,
thus permitting a load of greater weight than that for which each single
tram wire is intended to be carried over the system. One indisputable
claim for confidence in the flexible girder principle is said to be that,
although the peculiar combination of parts constitutes a striking and
valuable novelty, it contains nothing that has not been proved by the
experience of years--nay, generations--to be useful, economic, and
reliable. The usual practice followed in erecting suspension bridges is
applicable in mounting the line, and the carriers, supports, and
carriages may be of any of the usual forms. For the rapid removal of
limited loads wire tramways are in universal favor, and are recognized
not only as very economic and quickly constructed, but also as being in
many cases the only means of transport available except by the adoption
of elaborate and costly engineering works.
It has, it seems, been suggested by some who have examined the
construction of the flexible girder tramway for mineral and produce
traffic that it would be an additional advantage if arrangements were
made for the carriage of small loads--half a dozen or so--of passengers,
the primary intention being to carry the workpeople backward and forward
between comparatively inaccessible mines, works, or plantations and a
neighboring village or town. Compared with every other system where the
line over which the load travels is elevated, the flexible girder tramway
is claimed to possess many advantages--the center of gravity is kept well
down, the liability of the wheels leaving the line is reduced to the
minimum, the gradients are the easiest that can be obtained, there is an
entire absence of jolting and extremely little vibration, and the motion
is altogether smooth and regular; yet it is very questionable whether,
when human life is at stake, any but an ordinary ground line should be
relied upon. A living freight is far more liable than a dead freight to
move during the journey; and as the safety of all overhead lines depends
upon what is scientifically designated "unstable equilibrium," the
flexible girder tramway is not recommendable for passenger lines,
although it can, of course, be fitted for passenger traffic, a suitable
vehicle and ten or a dozen good stout workmen coming well
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