Evening star. [volume] (Washington, D.C.) 1854-1972, 1911-10-08


the increasing population. Had the
consumption increased each year at the
rate it did prior to 1907, the mean
daily rate for the present year would
have been about equal to the total sup
ply. and the maximum daily rate during
cold weather would have been some
thing like 120,000,000 gallons. This
would have meant daily demand of
30.000.000 gallons in excess of the sup
ply. The saving of all this water and
the averting Of a possible famine is said
to be due to remarkable little con-
trlvance known as a pitometer, which
has saved the District, during the four
years it has been used, more than
$4,000. figuring the cost Of water at
the rate of cents per 1000 gallons.
This little instrument is made up of
two parts, a photo-recording box and a
rod meter.
For the purpose of securing a reliable
record of the amount of water used in
any section of the city, the District is
divided into eighteen districts, and
throughout these subdivisions there are
scattered three hundred pitometer con-
nectionS. That is, there are that many
places where the pitometer can be at
tached to water mains, and the exact
volume of water flow aScertained for
any hour of the day. At these cOnnec-
tiOns the rod meter is inserted into the
main. and to it are attached two rubber
tubes, which connect with the photo
recording box. Affixed to the box is a
tube containing mercury. and the
water ascends through the tubes and
presses against the mercury it causes it to
move up and down as the flow of water
through the main. increases or decreases.
Every change in the position of the
mercury is registered by means of
- s@:A L, ,zsA
tive paper. These tests are made in
little box houses which entirely eX-
clude the light.
The pitometer is left at a station twen-
ty-four hours, when the records are
taken. If it is found that during the
last half of the night the water flow was
heavy. it is evident there was a leakage
somewhere and the water owls or pit
ometer squad set to work to find the
cause of the abnormal flow. The water
owls do their work while the city sleeps.
and from midnight until o'clock in the
morning move noiselessly about the
streets. listening here and there with the
aid of the aquaphone for the source Of
leakage.
Before the pitometer is set at connec-
ton every main leading to that particular
ing the District must pass through the
main to which the pitOmeter is connected.
This in no way disturbs the supply Of
water, and usually one main is sufficient
to meet the demands of any one district
at that time in the morning. Now that
a leakage has been discovered within the
cutoff territory the task of finding the
exact location of the flow is the next
step.
BY the aid of the aquaphone--an instru-
ment resembling a telephone receiver-the
pitometer squad is able to locate the
leakage The first tests are made from
the service pipes, that is, the pipes that
run from the mains to the houses. The
auuaphone is placed on the pipe through
a small opening in the pavement, and il
the sound of flowing water is heard the
supply is cut off at this juncture. If it
still continues to flow. it is evident the
leakage is located somewhere between
this point and the pitometer or along the
main.
These mains are buried from four to
thirty feet beneath the ground, and the
task of locating a leak in a main is
often a difficult one. The concrete is
broken so as to admit the end of a small
steel rod. This rod is driven in the
ground until 1t strikes the main, and
then the aquaphone is applied. If the
flow is near by the operator knows how