he other hand, it is suggestive, at least, of
misrepresentation for a summer hotel or boarding house to advertise that
their water-supply comes from springs when really it comes from an open
brook miles away from the spring which may be indeed the origin of the
brook, but with so many intervening opportunities for contamination that
the pure original source is unrecognizable.

There are two obvious drawbacks to the use of brooks: (1) that the
quality of the water is, in many cases, objectionable, and (2) that
brooks are very apt to dry up in summer on account of their limited
watersheds. The discussion on the first point will be postponed to a
later chapter, and we have now to consider the question of quantity
only.

The wisest plan before deciding on a brook supply is to measure the
volume of water which flows in the brook at the time when it is lowest,
probably about the middle of August. The actual volume of water needed
for the household is not large, although its required rate of flow may
be high and, as already pointed out, a stream which furnishes water at
the rate of one quart in five minutes is sufficient for a family of
three persons, a rate which is almost a drop-by-drop supply. Such a
stream would require a reservoir somewhere in order to supply the
faucets at the proper rate, and for a single family a small cistern or
even a barrel sunk in the ground would be sufficient for this purpose.
An objection to the utilization of so small a flow in connection with
the smaller storage is that the temperature of the water in summer is so
raised that vegetation and animal growths take place easily and freely,
so that the taste and smell of such water is most disagreeable. These
consequences can be avoided even with the low flow by increasing the
storage, since the larger quantity of water has been found to resist the
bad effects of the low flow and high temperature. Figure 35 shows a
small reservoir actually in use to supply water for a single house.

[Illustration: FIG. 35.--A reservoir for home use.]

_Storage reservoirs._

But even if the stream actually dries up for two or three months, it is
still possible to use it for water-supply, provided a suitable location
for a dam and pond can be found where storage, as described in the
preceding chapter, can be secured. For this reason as well as for the
greater benefit to the quality of the water, brooks flowing through
rough, wooded, and uninhabited country are to