Americus times-recorder. [volume] (Americus, Ga.) 1891-current, 1913-03-21

ldE nearL OF the united states,
but at point which is one Of
the nearest by transportation
routes to the countries of Central
and South America, is being built
a giant water power plant which must
greatly affect for good not only its i'm
mediate environment, the Mississippi
valley, but the whole nation and all
the nations in Pan America. The CO.
lossal size of the water power there
would cause appreciable effects any
where in the world, and it is located
almost exactly at the point where its
commercial influence may be exerted
most easily and effectively upon
world commerce.
The achievement nearing compile
ton is the damming of the mighty
Mississippi river, Harvesting it to tur-
bine wheels and electric generators
and distributing its tremendous power
over one hundred miles and more Of
the most efficient portion of the
United States on a direct traffic line
to the rest of the western hemisphere.
1t is not only an unparalleled engin-
eering achievement, but also perhaps
the greatest single economic force
flung into the world by the hand Of
man, excepting only the Panama
canal.
Nearly Mile Long.
The basis Of the water power de-
velopment at Keokuk, in the south
eastern corner Of the state of Iowa,
is a great daR extending for nine
tenths of mile from the Illinois bluff
to its junction with the titanic pow
er house near the Iowa shore. This
dam is a composite structure of 119
arched spans, all alike, with piers six
feet thick thirty feet apart, and spill
ways in the spans, all alike, over
which the water will flow. This dam
is monolith of massive concrete set
down several feet into the hard rock
bottom of the Mississippi, but i'm
pounding the water by its immense
weight. The structure, with the ex-
terror appearance Of a bridge, is 81
feet high, AZ feet wide at the bottom,
and 20 feet wide on top; the spillways
between the piers are 80 feet high, fill
the width of the dam at the bottom,
have vertical upstream faces, and
their downstream face is an ogee
curve which delivers the water at the
bottom horizontally to the river cur
rent On top of each spillway will be
q steel gate II feet high. BY varying
~ xxybi
open and closed, the amount of water
flowing over the dam will be regulat-
ed, with the result that at varying
stages Of the river the pool above the
dam will have always an unvarying
depth and it's surface will always re-
main at the same place.
The water wheel itself is another
example of overcoming the impossi-
BILE, for experts said that it was i'm
possible to build a turbine which
would meet the unusual conditions
there. But Chief Engineer Cooper
called a council of war and little
later rose from the head of that table
with a new design of turbine which
tests show has So per cent OF eff
cheney as compared with the next best
result ever attained of 80 per cent.
and textbook figure of rs per cent.
of efficiency as the norm to be used
in engineering calculations. The 80
turbine wheels in the Keokuk power
house are several times as large in
dimensions as any ever made before.
Each is at the lower end of shaft 25
inches in diameter, on the upper end
of which is the revolving part of the
electric generator standing on the
power-house floor. The revolving
shaft. with its machines at each end,
weighs about $4,000 pounds. and it
is supported on one bearing which is
fabricated by forcing oil between its
surfaces at a pressure of $50 pounds
to the square inch. From this bear
ing a steel cone carries the weight to
a huge ring below, and the total
weight of one turbine unit is about
1872. 900 pounds. The lower ring itself
weighs about ILL., 900 pounds, and be-
tween 1t and an upper ring OF similar
size is a steel cylinder embedded in
the massive concrete, which is the
basement of the power house. The 80
turbines develop over 100000 horse
power, and this is increased by two
auxiliary smaller wheels. which also
energize the exciters OF the electric
generators. This is over three times
as much power as Is developed in any
one other water-power plant In the
world After deducting slight losses
of energy and very large reserve
200, 900 horsepower will be sold for
commercial use.
At the lower end of the great power
house is a colossal lock with the same
width as those at Panama and with
lift of 40 feet instead of the lift OF 70
feet 4 inches in any one lock at the
canal. Beside the lock will be a NAM
moth dry dock for building and re-