drunk for twelve hours.

The purity of drinking water is a matter of much importance. That which
contains a minute quantity of lead will give rise to all the symptoms of
lead poisoning, if the use of it be sufficiently prolonged. An account
is given of the poisoning of the royal family of France, many of whom
suffered from this cause when in exile at Claremont. The amount of lead
was only one grain in the gallon. Care should therefore be taken to
avoid drinking the water which has been contained in leaden pipes. It
should always be allowed to run a few minutes before being used.

An excess of saline ingredients, which in small quantities are harmless,
frequently produces marked disorders of the digestive organs. A small
amount of putrescent matter habitually introduced into the system, as in
the use of food, is productive of the most serious results, which can be
traced to the direct action of the poison introduced. A case is recorded
of a certain locality favorably situated with regard to the access of
pure air, where an epidemic of fever broke out much to the astonishment
of the inhabitants. Upon observation it was found that the attacks of
fever were limited to those families who used water from a neighboring
well. The disagreeable taste of the water which had been observed, was
subsequently traced to the bursting of a sewer, which had discharged a
part of its contents into the well. When the cause was removed, there
was no recurrence of the evil effects.

ORGANIC IMPURITIES. "Water is liable to organic contamination from a
multitude of causes, such as drainage from dwellings, dust, insects, the
decaying of vegetable and animal matter. These impurities may be
mechanically suspended or held in solution in the water. Although
organic impurities, which are mechanically suspended in water, are
poisonous, yet they are generally associated with animalculea, and these
feed upon, and finally consume them. Good water never contains
animalculae. They are never found in freshly fallen rain-water, remote
from dwellings, but abound, to a greater or less extent in cisterns,
marshes, ponds, and rivers. These little workers serve a useful purpose
since they consume the dead organic matter from the water, and, having
fulfilled their mission, sink to the bottom and die. Water which
contains organic matter is exceedingly dangerous to health, and its use
should be carefully avoided.

In low lands where the current of streams is slug