will be the more readily appreciated when it is considered that with a
given load on a gradient of 1 in 30 the resistance due to gravity alone
is 200 per cent. greater than on a gradient of 1 in 150, and that the
retardation and wear and tear due to friction, greater curves, and
imperfections increase still more rapidly with increase of gradient, soon
rendering the old sagging wire line practically worthless.

To construct an entire line of flexible girders would be not only
unnecessary, but so costly as to neutralize any advantage which it may
possess, yet for surmounting occasional obstacles the claim made for
it--that it will sometimes permit of a line otherwise impracticable being
cheaply made--seems justified. One can readily imagine a light narrow
gauge line costing £1,000 per mile being laid, for example, between a
mine and the shipping place, and that a swamp, river, or valley would
cost more to bridge over than the whole line besides. If at this obstacle
the trucks or carriages could be lifted bodily, passed along the flexible
girder, and again placed on the line the other side of the obstacle, the
advantage to be derived is obvious; and as the flexible girder is really
little more than a suspension bridge _minus_ the platform, and having but
two suspension wires, the cost and the difficulties should both be very
small.--_Industrial Review_.

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BOZERIAN'S REFRIGERANT PUNKAS.