d to make the
necessary detour himself, passing into the middle of the thoroughfare
and there outstripping the party in front, without the assistance of
the guide-rail, and rejoining the track.

To execute this movement, of course, the motor wheels for the
guide-tracks must be mounted on entirely different principles from
those adapted for railroad traffic. The broad and soft tyred wheels
which bear upon the asphalt track will be entrusted with the duty of
carrying the machine without extraneous aid; but there will be two
extra wheels, one in front and one at the rear, capable of being
lifted at any time by means of a lever controlled by the driver. These
guiding wheels will fit into the groove of the tram line in the
centre, being made of a shape suitable for enabling the driver to pick
up the groove quickly whenever he pleases. The carrying wheels of the
vehicle in this system are enabled to pass over the guide-rail
readily, because the latter does not stand up from the track like the
line in a railroad.

A simpler plan, particularly adapted for roads which are to have only
a single guide-rail, is to place the rail at the off-side of the
track, and to raise it a few inches from the ground. The wheels for
the rail are attached to arms which can be raised and lifted off the
rail by the driver operating a lever. Guiding irons, forming an
inverted Y, are placed below the bearings of the wheels to facilitate
the picking up of the rail, their effect being that, if the driver
places his vehicle in approximately the position for engaging the side
wheels with the rail and then goes slowly ahead, he will very quickly
be drawn into the correct alignment. Of course the rails for this kind
of track can be very light and inexpensive in comparison with those
required for railroads on which the whole weight of each vehicle, as
well as the lateral strain caused by its guidance, must fall upon the
rail itself.

The asphalt track and its equivalent will be the means of bringing
much nearer to fulfilment the dream of having "a railway to every
man's door". Many such tracks will be equipped with electric cables as
well as guiding-rails, so that cars with electric motors will be
available for running on them, and the power will be supplied from a
publicly-maintained station. Some difficulty may at first be
experienced in adjusting the rates and modes of payment for the
facilities thus offered; but a convenient precedent is present to h