nting a total weight of
20 tons.

It is impossible to enumerate in this paper all the various kinds of
wagons and trucks suitable for the service of iron works, shipyards,
mines, quarries, forests, and many other kinds of works; and we
therefore limit ourselves to mentioning only a few instances which
suffice to show that the narrow gauge can be applied to works of the
most varied nature and under the most adverse circumstances possible.

It therefore only remains to mention the various accessories which have
been invented for the purpose of completing the system. They consist of
off-railers, crossings, turntables, etc.

The off railer is used for establishing a portable line, at any point,
diverging to the right or left of a permanent line, and for transferring
traffic to it without interruption. It consists of a miniature inclined
plane, of the same height at one end as the rail, tapering off regularly
by degrees toward the other end. It is only necessary to place the
off-railer (which, like all the lengths of rail of this system, forms
but one piece with its sleepers and fish-plates) on the fixed line,
adding a curve in the direction it is intended to go, and push the
wagons on to the off-railer, when they will gradually leave the fixed
line and pass on the new track.

The switches consist of a rail-end 49 in. in length, which serves as a
movable tongue, placed in front of a complete crossing, the rails of
which have a radius of 4, 6, or 8 meters; a push with the foot suffices
to alter the switch. There are four different models of crossings
constructed for each radius, viz.:

1. For two tracks with symmetrical divergence.

2. For a curve to the right and a straight track.

3. For a curve to the left and a straight track.

4. For a meeting of three tracks.

When a fixed line is used, it is better to replace the movable switch by
a fixed cast-iron switch, and to let the workmen who drive the wagon
push it in the direction required. Planed switch tongues are also used,
having the shape of those employed on the normal tracks, especially for
the passage of small engines; the switches are, in this case, completed
by the application of a hand lever.

The portable turntable consists of two faced plates laid over the other,
one of thick sheet iron, and the other of cast iron. The sheet-iron
plate is fitted with a pivot, around which the cast iron one is made to
revolve; these plates may either be smooth, or groov