What is known about the history of the cogwheel in simple terms?

Hi, 

Archimedes, Greek mathematician (Syracuse 287 to 212 B.C.)
Son of Pheidias, the astronomer who calculated the relative dimensions
of the sun and the moon, Archimedes who grew up in Alexandria where he
became a student of Euclid, invented the cog wheel or what we know
today as the cog gear.

In his first book, On the equilibrium of planes, he analyzed the
theory of the lever, only requiring " one pressure point to move the
world ". He foresaw the helix, invented the archimedean screw, the
running or pulley block and the cog wheel.

Leonardo da Vinci

Leonardo sought new possibilities for transforming rotary motion into
see-saw motion, an essential element of any machine. With this aim in
view, he experimented with gears, hoists, cranks and cog-wheels. He
made use of wind energy and muscular force, the spring drive and the
flywheel. Among other devices, he invented hydraulic machines and
clock-making mechanisms as well as swing bridges and the printing
press.

Basics of a Gear or Cog Wheel

A cog gear is a toothed wheel designed to transmit torque to another
gear or toothed component. The teeth of a cog gear are shaped to
minimize wear, vibration and noise, and to maximize the efficiency of
power transmission.

Different-sized gears are often used in pairs, allowing the torque of
the driving gear to produce a larger torque in the driven gear at
lower speed, or a smaller torque at higher speed.


Resources

Archimedes Home Page
http://www.mcs.drexel.edu/~crorres/Archimedes/contents.html

Amazing Gears of History
http://www.nordex.com/htmlpages/amazing.html

Gears: History
http://www.efunda.com/DesignStandards/gears/gears_history.cfm


thanks, 

webadept-ga

---

Clarification of Answer by webadept-ga on 31 Dec 2004 00:42 PST

Hi, I did not cite two of my sources properly, a mistake on my part.

Please Note that other referances are 
Encyclopedia
http://www.novosoft-online.com/encyclopedia_us.htm

and Gianadda, Fondation Pierre Giana
http://www.gianadda.ch/e/expos/F_M_expos_vinci.html

The words of Leonarod Da Vinci can be seen here
http://www.leonardo.net/gallery.html#start

thanks, 

webadept-ga

A very helpful direct answer with relevant references that I will follow up.