ected water is not found. The city supply of Ithaca, New York, is a
case in point. For six miles south of the lake there is a broad, almost
level valley filled many hundred feet deep with glacial drift and
presumably filled with water flowing at some unknown depth below the
surface into the lake. When the city was recovering from the typhoid
fever epidemic which, in 1903, committed such ravages, well water seemed
to the panic-stricken citizens the only safe water. Geologists were
called in, and they gravely asserted that the valley contained glacial
drift to a great depth and that an ample supply of pure water could be
counted on. It was known that water was met all through this valley at
depths of from six to twelve feet and then that there would be found a
layer of finely powdered silt to a depth of about one hundred feet, when
another layer of water would be found, and that all the private wells
reached this layer. When tested by the city, however, it was found that
this water-bearing stratum was of too fine material to yield its water
freely, and the supply from the depth was altogether inadequate. In one
section of the town large quantities of good water were found at a depth
of about three hundred feet, and the city thought that other wells of
the same depth should add to the quantity, but experiment showed that
this three hundred-foot water was limited to one particular section, and
after a considerable expenditure of money, an underground water-supply
for the city was given up.

_Ordinary dug well._

The ordinary well at a farmhouse is what is known as a shallow well or
sometimes a "dug well," usually ten to twenty feet deep. This type does
not usually pierce any impervious layer and thus reach a water-bearing
stratum, otherwise inaccessible. The water is found almost at the
surface, and the depth of the well is only that necessary to reach the
first water layer. A very good example of this kind of well is to be
found on the south shores of Long Island Sound, where a pipe can be
driven into the sand at any point, and at a depth of a few feet an
abundant and cheap supply of water may be secured. The amount of water
that such a well can furnish depends upon the area from which the water
comes and upon the size of the particles of sand or gravel through which
the water has to percolate, it being evident that the finer the
material, the more difficult for the water to penetrate.

The writer remembers superintendin