Thank you so much for your input and for the most interesting drawing, Jasper.
Pity that it is rather small; wish you could provide me with a larger one, for my archives
Mind you, this chamber was not acquired in Portugal, but bought in an international seller. So i thought the probabilities for this example being Portuguese were remote. As it was reputed by the seller to have been found in the sea of Cortez, i would admit it could be Spanish, the ones to whom this half of the world pertained, but you know how sellers may be misinformed. It is always terrible to identify items that are not marked. Not the same as with the Portuguese cannons of the period, like this typical bronze "Berço" Manuelino, from around 1500, with the royal arms and the traditional globe, a symbol favoured by King Dom Manuel.
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