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Al-Jazari (1136 – 1206) mostly made small modifications to devices invented by the Greeks, Romans and Byzantines.
Instead of a Roman god slaying a bull, a statue of a servant handed a towel and a comb to the king.
Al-Jazari’s float valve was copied from a Jewish inventor named Philo of Alexandria.
See other posts for his pumps and water clocks.
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Hero (or Heron) of Alexandria
See the devices at https://www.youtube.com/watch?v=GrI1FsH4UH8
[The video is followed 15 seconds later by a video on Chinese inventions. The Muslims did not borrow as much from the Chinese because Muslims did not have as much contact with Chinese technology.]
For more examples of inventions of Hero of Alexandria, search YouTube for “hero of alexandria” or “heron of alexandria”.
Hero created an entire play of robotic statues and automated scenery backdrops programmed by ropes, knots, and the weight of sand leaving a hopper.
Al-Jazari (1136 – 1206) made small modifications to devices invented by the Greeks, Romans and Byzantines.
Al-Jazari’s robotic gadgets (some of them steam-driven) used the same technology as Hero (called Heron in England) of Alexandria had used many centuries earlier, but with different themes. Instead of a Roman god slaying a bull, a statue of a servant handed a towel and a comb to the king.
Al-Jazari built a sink that used a float valve to shut off further flow of water into the sink when the sink was full. This used the same principle as the float valve in modern toilet tanks. But al-Jazari was not the inventor; it was actually a Jewish invention. Al-Jazari borrowed the design from “The Book of Ingenious Devices” by the (Muslim) Banu Musa brothers. In chapter 75, the Banu Musa brothers provide a diagram of the device and state “… when float (t) rises as the water runs into tank (m) the tap turns and closes. We make its closing position when the water in tank (m) reaches position (s)”. According to Prager and Woodcroft, the construction and the effects of invention 75 of the Banu Musa brothers is very similar to the constantly refilled vessel invention in chapters 17, 18 and 19 of “Pneumatics” by Philo of Alexandria http://books.google.com/books?id=MdpAo6SaOL0C&pg=PA21&lpg=PA20&ots=4NcRfYuHR6&focus=viewport&dq=prager+woodcroft&output=html_text
Philo of Alexandria was an early 1st century Hellenized Jew living in Alexandria in the Roman Empire. [Philo of Alexandria was not the same person as Philo of Byzantium.]
Float valves, siphons were known about in pre-Islamic times.
DEVICES WITH GEARS
Gear ratios were used by Ctesibius in the Roman/Greek city of Alexandria Egypt.
The calculating instrument called an equatorium (invented in the 5th century by a Greek named Proclus) was not a Muslim analog computer http://en.wikipedia.org/wiki/Equatorium
If was not as sophisticated as the mechanical device with many gears, built by Greeks in 150 BC, that may have predicted the dates of lunar and solar eclipses. http://www.pbs.org/wgbh/nova/ancient/ancient-computer.html .
Al-Biruni (973-1048) built a mechanical device with a train of gears to illustrate the motion of the sun and planets around the Earth, which might be the reason en.wikipedia refers to him as a “pioneer of experimental mechanics”. [A train of gears with a 360:1 gear ratio was used as early as the 3rd century BC to turn the day-of-the-year mechanism in a water clock built by Ctesibius.]
Hero of Alexandria built a steam engine called the aeolipile in which 4 pipes stuck out from a sphere, the 4 pipes each bent 90 degrees at the end. (He also wrote about a version of it that had only 2 pipes.) When a temple priest lit a fire under the sphere, the stage on which stood statues of dancing goddesses would magically rotate.
Al-Jazari copied the 4 pipe version, using it to rotate the meat on a spit.
Al-Jazari copied from Heron of Alexandria the technology to make “robots” that moved their arms and legs and played musical instruments. http://www.youtube.com/watch?v=qXDwYd6F7-A
Abbas ibn Firnas (810 – 887) built a machine (likely copied from a machine built by Hero of Alexandria) that produced thunder sounds by dropping balls. Hero had designed it for a temple of the god Zeus.
MERCURY AS A LUBRICANT
The claim Al-Jazari used mercury instead of grease as lubrication could be true only if the surface of the gears were made of gold.
Al-Jazari made objects of copper coated in tin, but Pliny the Elder in the first century had written of metal objects being dipped in molten tin to prevent corrosion.
Al-Jazari did not invent the combination lock (the type used today on briefcases), which had been used by the ancient Chinese and by the Romans.
PEN WITH INK RESERVOIR
A pen with an ink reservoir was presented in 973 AD to Ma’ād al-Mu’izz (931- 975), the caliph of the Maghreb. It could be held upside-down without leaking. No one repeated producing this device; perhaps it did not work well.
Image by unknown 17th century artist, via Wikimedia Commons.
image credit https://en.wikipedia.org/wiki/File:Hero_of_Alexandria.png