Archimedes' Screw has been used to lift water to higher
levels since ancient times. Archimedes (287-212 B.C.) is the traditional inventor
of this device, which was originally used for irrigation in the Nile delta
and for pumping out ships. I have seen a nineteenth century Archimedes' screw
still at work pumping water in a windmill at Schermerhoorn in the province
of North Holland in the Netherlands. It lifted the water a vertical distance
of 1 meter.
An analysis, using the lifting of marbles instead
of water, is used in almost all nineteenth century texts. The lower end of
the helical tube dips into a dish of marbles and scoops one up. The helix
continues to revolve, and the marble is continually being lifted a short
distance up an inclined plane. The frictional forces are small, and the marble
keeps rolling down an infinite succession of inclined planes formed by the
revolving helix. At the same time the marble resides at the local low spot
on the helix, and is carried up the slope by forces perpendicular to its
local motion.
The model Archimedes' Screw at the top right
is in the Smithsonian Institution collection, and was sold by Queen in 1867
at $5.00.
The middle right example is by Benjamin Pike,
Jr. of New York, and and is $9.00 in the 1866 catalogue. It is at Transylvania
University in Lexington, Kentucky.
At the bottom right is an Archimedes' screw demonstration
from the United States Military Academy at West Point. This was made by Pixii
of Paris, and bought by the Academy in 1829. The example below is also by
Pixii, and is in the Smithsonian Institution collection.
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