The farmer and mechanic. [volume] (Raleigh, N.C.) 18??-19??, 1909-03-09

= 80 0oS Ill
hill, back to the sea. Water wheels
are but devices to catch and utilize !
this energy which ordinarily is wasted
on the unmoving rocks and stones.
water acts as a moving power, either
by its weight, which is over sixty-twoI
pounds,t to the cube foot, or by it's pres
sure or impact. The power Of a fail
OF water is equal to the weight Of its
volume and the vertical height Of it's
fall. To. compute the power Of fail
ing water it is necessary to multiply
the volume Of flowing water in cube
feet per minute by its weight, 62.5
pounds. and this product by the verti-
cal height Of the fall in feet. Thu a
Weir five feet in width by one DOT IL
depth and having a fall of twenty feet
develops 1871 horsepower.
It is easy nough to Weir a small
stream. A rough plank lam is made.
between h banks. One end is liked
With a slide SO the rectangular aper-
ture can be widened until the water
flows Just a foot deep over the edge
Of the topmost plank. Knowing the
width of the aperture in linear feet
one can figure out the number OF cubic
feet of water flowing in the stream
per minute. In larger streams the
flow can only be computed by sound
ings for the average depth and using
floats to determine the flow.
But the water-DoWer Of a stream
must not be computed at a time when
the stream is swollen by heavy rains
because the horsepower Will not be
there during the summer season when
rains are not SO plentiful. A large
numbe Of streams, whose sources are
~ ~snoW-capped mountains or in great
IN maintain almost a constant
flow the year around. Others get
very low during July OF August. To
secure a reliable and permanent source
OF power i'll a small stream which runs
low during the summer it is necessary
to build storage reservoirs to store up
the water, which usually runs quickly
to waste after q heavy rain. SO it can
be used when needed. Swamps and
s~noW-capped mountains are in hem
selves storage reservoirs.
1t is possible in these days Of scien-
tific research to determine very accu-
rately the amount of power available
In any given stream. Weiring the
stream during the summer months will
sho" its average flow. A transit in
the hands of q surveyor Will quickly
show the number of feet of fall avail
able for any distance. The surveyor
can also ascertain the number OF acres
in the watershed. and, by writing the
weather bureau, at Washington. the
average rainfall in that section for the
season can be determined, showing
| just how much water goes to waste III
the spring freshets and just 0 large
a reservoir will be needed to store
lHaL wafer lot use during the uiE
months. Then anyone with a head
for simple figures can determine the
amount OF power available and he
probable cost Ct the equipment.
So important is the development of
water-power in this country that the
General Electric Company and other
large electrical concerns maintain a
large staff of engineers whose duties
are to examine prospective water
power developments for e~nterprising
men who plan to harness the rivers
and streams.
streams is a very simple matter now
compared to what it was a few years
ago. All the new dams are made Of
concrete. Rough board forms
are constructed where the dam
is needed and the concrete is sim
ply mixed and dumped into the
moulds and allowed to harden. These
dams do not cost anywhere near as
much as stone masonry and can be
erected in a comparatively short time.
It is argued tina the destruction of
the forests has impaired the water
power Of the country. This is true to
q, certain extent. in that the forests
formerly acted as storage reservoirs,
or giant sponges, which held the water
back and kept the streams from sud
den rise during heavy rains and from
becoming very law When it rained nOt
at all. This damage car be remedied
by constructing artificial reservoirs.
Water-Wheels of the very latest
pattern are now made in all sizes
from the little fellow which fastens on
the house-taD to drive the sewing ma
chine to the giant turbine capable of
turning Niagara's thousands Of horse
power into electricity for Buffalo,, Nj
agara Falls, Rochester, Syracuse, and
Toronto. The water wheel is connect
ed SO as to drive an electrical genera
tor which changes the energy into
electricity SO it can be transmitted
reasonable distance to be used for
power, light and heat.
OF course one hears a great deal
labOI,t the W~ater-DOwer DEVELOPMENTS