ger number of barges can be hauled, while the
progress made is definite and there is no drifting back, as occurs with
paddle or screw tugs when they have temporarily to slow or stop their
engines on account of passing vessels. Several streams, as the Elbe,
Rhine, and Rhone, have now such cables laid for long distances in those
parts of the rivers where the traffic is sufficient to warrant the
adoption of the system. While this has been introduced only during the
last 16 or 18 years, a similar method of transporting merchandise has been
in use in Russia on the river Volga for upward of 40 years. Navigation on
this river is interrupted for about half the year by the ice, and the
traffic is of larger amount only during part of the summer, while the
length of the river itself is very great, so that laying down permanent
cables would not pay; while, on the other hand, the current is so strong
that towage of some sort must be resorted to for the transport of large
quantities. The problem has been solved by the introduction of the capstan
navigation or towage.

[Illustration: CAPSTAN NAVIGATION ON THE VOLGA.]

There are two kinds of capstans in use, one actuated by horse-power and
the other by steam engines. A horse capstan boat carries according to size
150 to 200 horses, which are stabled in the hold. On deck a number of
horse gears are arranged at which the horses work. The power of the
separate gears is transmitted to a main shaft, which is connected to the
drums that wind on the rope. The horses work under an awning to protect
them from the burning sunshine, and are changed every three hours. Eight
and sometimes ten horses work at each horse gear. The horses are changed
without interruption of the work, the gears being disengaged from the main
shaft in rotation and the horses taken out and put in while the gear is
standing. The horses are bought at the place of departure in the south of
Russia and resold at the destination, usually Nishny-Novgorod, at a fair
profit, the capstan boat carrying fodder and provender for the attendants.
The capstan is accompanied by a steam launch which carries the anchor and
hawser forward in advance of the capstan. The latter has a diameter of as
much as 5 in., and is two to three miles in length. The anchor is dropped
by the tug and the hawser carried back to the capstan, where it is
attached to one of the rope drums, and the boat with the barges attached
to it towed along by the horse gear