A couple of observations/questions about the rotary mortar.  Seems like a low angle for a mortar, wonder how they changed the elevation?  Normally when you load a mortar you do it without a patch or sabot, but if you didn't with this gun the shells would roll out on the low side of the wheel.  I wonder how long it took to load, and how did they fire it without having a chain fire?  My guess is that this wasn't too effective or there would have been more of them.  You are right Mike and Tracy, it would draw a crowd.