17" stone mortar at USNA

[cannonmn]

I call this mortar "El Gordo" even though it has no given name. It was designed to fire large baskets filled with stones, or alternately, with a basket of time-fuzed explosive cannon shells. The purpose was to break up groups of enemy troops who were storming your fort.

http://s17.photobucket.com/albums/b62/cannonmn/miscforumsetc/forums50/?action=view&current=1c3f1319.pbw

[Soot]

Why does it have what looks to be rust on it, assuming that it's a bronze mortar?

[Cannoneer]

Alright, let's see if I've managed to learn anything from you, without getting it jumbled. The left trunnion (which is very clear) informs us that the copper used to make this mortar was mined in Mexico and Peru. I think those are numbers on the right trunnion; would these be designating the weight of this piece? I can't make out what's contained in the ribbon that goes around the breech, and edges the tops of the trunnions, but wouldn't that usually give the location of the foundry, and the date the tube was cast? You say that you've dubbed the mortar 'El Gordo'; isn't it unusual that an example of Spanish ordnance of this time period, doesn't have a name marked on it?

[cannonmn]

The banner says it was cast in Seville in 1779?.  It gives the day of the month and the heat number also.  The other trunnion mark is the weight, yes.  There was a period in late 18th C. when mortars were not given names, not sure why.  The red is all from a US 15-in. round shot that I found across the river and had on my desk as a paperweight, then the day before graduation, I was told the ball had to go away for me to graduate.  I got some classmates together and we dropped it in the 17 in. mortar to make it disappear.  It rusted for years before being removed, and the rust in the overflowing rainwater stained the mortar somewhat.  I left my mark.