the masonry. If
the mill is set directly over the well and the storage tank supported on
the tower, a very compact arrangement is accomplished and the danger
from frost is the only difficulty to be apprehended. However, the tank
is often placed in the attic, some distance from the well, to which it
is connected by suitable piping.

The location of the windmill requires careful consideration in order
that it may receive the prevailing winds in their full force and at the
same time be properly located with reference to the well. It must be
remembered that the surface of the wheel is exposed to the full fury of
a storm, and both the wheel and the tower must be strong enough to
withstand such storms. Figure 43 shows windmill and water tank in the
vicinity of Ithaca, New York.

_Hydraulic rams._

A hydraulic ram is the cheapest method of pumping water, provided that
the necessary flow with a sufficient head to do the work is available.
It requires about seven times as much water to flow through the ram and
be wasted as is pumped, so that if it is desired to pump five hundred
gallons a day, the stream must flow at the rate of about thirty-five
hundred gallons per day to lift the necessary water.

The two disadvantages of a ram are, first, that a fall of water is not
always obtainable or that the stream flow is not always sufficient, and
second, that the action of the ram is subject to interruptions on
account of the accumulation of air in summer and on account of the
formation of ice in winter. In fact, in winter it is necessary to keep
a small fire going in the house where the ram is at work in order that
this interruption may not take place. Its great advantage is that it
requires no attendance, no expense for maintenance, and practically
nothing for repairs. It operates continuously when once started, and,
except for the occasional interruption on account of air-lock, is always
on duty.

[Illustration: FIG. 44.--Installation of ram.]

Usually the water is led from above the dam or waterfall in a pipe to
the ram and flows away after passing through the ram, back into the
stream. The water pumped is generally taken from the same stream and is
a part of the water used to operate the ram. This is not necessary,
however, and double-acting rams are manufactured which will pump a
supply of water from a source entirely different from that which
operates the ram. The following table from the Rife Hydraulic Engine
Manufactu