Curious stone cannon

[fernando]

Originally Posted by Hotspur

The one in the back to lock the breech block?

Cheers

GC

As i approached in post #6.
To my unexperienced eye, the hole in the back seems to be horizontal.
I reckon i see various holes but only one touch hole.
Also the breech cavity doesn't seem to accomodate a classic rotating cilindrical re(chamber), but rather a squared frame for a lid.
There ought to be an explanation for such an atypical system.

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