Hi Jim,
While Michl doesn't come in, asssuming he will
, let me post a few notes i gathered on these things.
It appears that these pots were used for a zillion purposes; gunpowder testers, celebration mortars, signaling devices, whether to guide sailors through fog, saluting when entering ports, signaling manoeuvers when in battle, trap setups to blast the enemy when assaulting fortification gates, noise makers to cause impression ... you name it.
In the chapter of signaling, i beleive these were alternated with actual cannons ... in the beginning, actual ordnance ones and later miniature ones.
Just 'en passant', Vasco da Gama during the discoveries period used the following code: one cannon shot for continuing ahead, two for turning, three for hoisting the "moneta", an apendix sail to increase the speed and four shots for slowing down. But i am digressing here
.
You might as well be on the right track about the Christian crosses on this example, but my view is distinct . I think the crosses are there basically to identify the mortar as Church property, admittedly seconded by the ever present spiritual touch, and that it was kept for using in religious festivities and not for belligerent purposes. Such is also the conviction of the (French) seller.
Now, let us see what Michl thinks of all this ... as well as other forumites, naturally.
Here attached, the picture of a most interesting cannon trap, used in (French) citadel gates during the XVIII century.
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