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Originally Posted by nKante
Elastic bands or bendable fork?
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I can find no early references to the construction of the catapult bands. Bendable forks are unlikely as they are too short to generate sufficent power to propel a stone. Sinew, although slightly elastic, would not 'accellerate' fast enough (after being pulled) to give any momentum to the missile either.
Rubber is almost certainly the only possible material that could be used.
Although primative societies used the sap from 'rubber' producing trees/plants, it was not the rubber we know today. It's properties were badly affected by heat and moisture and although 'stretchy' was weak, so would not have been suitable for catapult 'bands'. This early form of rubber tended to be used to waterproof clothing etc.
In 1839, C.Goodyear dropped (accidentally) a mixture of rubber, white lead and sulphur upon a hot stove. When it was removed, the material was no longer affected by temperature. Despite stretching, it always returned to its original shape. This was known as vulcanisation, this is probably the earliest date that catapult 'bands' were actually possible. And would only be available to 'industrialised' societies.
The catapult 'bands' requires a material which will stretch and when released....will return to its original dimensions ......as QUICKLY as possible. This generates the accelleration required to give a missile the necessary momentum. Modern catapults use silicon rubber, which is superior to the 'classic' rubber previously used. The amount of effort to pull back the sling (and bands) is minimal......but the power generated by the 'release' is far greater.... and can easily propel a ball bearing through a car door......
I know ...because I have one .......and have tested it .... safely.....
