History Gear

single-stage gear reducer

examples of gear applications include:

ma jun (c. 200–265 ad) used differential gears part of south-pointing chariot.
the first geared mechanical clocks built in china in 725.
al-jazari (c. 1206) invented segmental gear part of water-lifting device.
the worm gear invented part of roller cotton gin in indian subcontinent (c. 13th–14th centuries).
the 1386 salisbury cathedral clock may world s oldest still working geared mechanical clock.




^ derek j. de solla price, on origin of clockwork, perpetual motion devices, , compass, p.84
^ antikythera mechanism research project: why important? . retrieved 2011-01-10. mechanism thought date between 150 , 100 bc 
^ norton 2004, p. 462
^ lewis, m. j. t. (1993). gearing in ancient world . endeavour. 17 (3): 110–115. doi:10.1016/0160-9327(93)90099-o. 
^ joseph needham (1986). science , civilization in china: volume 4, part 2, page 298. taipei: caves books, ltd.
^ segment gear, thefreedictionary.com
^ donald hill (2012), book of knowledge of ingenious mechanical devices, page 273, springer science + business media
^ irfan habib, economic history of medieval india, 1200-1500, page 53, pearson education