timate of
the water used would be twenty-five gallons per head per day. This
amount must be multiplied by a maximum number of persons to be in the
house at any time, and then this number must be increased by the amount
of water used in the barn and in the yard, if these are to be supplied
from the same source as the house.

_Quantity used in stables._

The amount of water used in the barn is even more than that used in the
house, a variant depending on the habits of the manager. The minimum
quantity needed per day is determined by the number of pailfuls of water
which each head actually drinks multiplied by the number of head. But
besides this there are many other uses to which water may reasonably be
put in connection with stock.

On a dairy farm, there is the water needed to wash cans and bottles and
in some cases to furnish a running stream of cold water for the aerator.
In some stables a large amount of water is used for washing harnesses
and carriages; in others, but a small amount goes for such purposes.
Some farmers have concrete floors in cow stables and pig pens and use a
hose frequently to wash these floors clean. Other stables never see a
stream of water and only see a shovel at infrequent intervals. The
amount of water used outside the house is too uncertain a quantity to
estimate on the average, but its influence and importance must not be
overlooked.

_Maximum rate of water-use._

It should now be noted that the quantity of water already referred to is
the average quantity used through the twenty-four hours and does not
mean the rate at which the water comes from the faucet. For example,
three persons in a house use water, according to the above statement, at
the rate of seventy-five gallons per day, but a whole day has 1440
minutes, and if seventy-five gallons be divided equally among the number
of minutes, it means one gallon in every twenty minutes, or one quart in
five minutes. It is obvious that no water-supply system for a house,
designed to supply water at the average rate for the twenty-four hours
would be satisfactory, since no person would care to wait all day for
the amount. To wait five minutes to draw a quart of water would try the
patience of any one, and while the total amount of water used in the
house will be seventy-five gallons, provision must be made by which it
can be drawn in small amounts at much higher rates. Practically all of
the amount is used in the daylight hours or in tw