Robert you may be right about the dripping water. How one would have used the gas created I do not know but that is the genius in simple processes.
http://en.wikipedia.org/wiki/Acetylene
It has just come to me like a bolt of lightening. They make licquid Acetylene then use a low pressure primus stove type of torch simple. How dumb am I

. The sword could be 19th century. Skilled work

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