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Originally Posted by fernando
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But you've made my day, though. This is the first time i see an English speaker spelling the word 'vinho' ... in strictly correct Portuguese  .
Best
Fernando |
Ah Fernando ....its almost a duty for an Englishman to know how to order a drink in any foreign land
........Cheers
Thank you for posting the pictures, the silk wrapped Chinese cannon is very interesting. The barrel looks metallic ...but has a thin walled barrel. Obviously the 'silk' wrapping adds strength to the barrel...and would assume this made it much lighter, making it easier to carry. A travelling army could 'carry' a larger number of such cannons than the 'normal' metal barrelled type .....more 'fire power' for the 'same' weight.
The tensile strength of silk is quite high (500 MPa) in comparison brass is 200+ MPa , copper is 70 MPa, cast iron is 130 MPa, Steel, high strength alloy is 690 MPa and Steel (AISI 1060 0.6% carbon) Piano wire is 2200-2482 MPa
I would assume that the leather and rope cannons were formed using the materials 'wet', as both materials would 'shrink and tighten' significantly once fully dry. This would mean the rope 'binding' would be extremely tight and pre-stressed....making the structure quite rigid and limiting any flexibility.
Regards David