Pacemaker Boat Owners Association

I have a 1970 33ft Convertable Sedan. 350 engines, Velvet drive trannys (1.91-1 reduction). This past weekend I went up to start winterizing the boat, When i pulled the engine cover off of the port engine, I noticed that the engine "catch pan" had tranny fluid in it.I checked the dipstick and the tranny fluid was below the "low" mark. This was not there the last time i was up to the boat (it's 4 hours away from me) it's been about 6 weeks. Any ideas what would cause a tranny leak when the boat isn't running? Another "issue" that i found,(I don't know the part names, so I'll try to describe them) on the back of the tranny, the driveshaft comes out and connects to another shaft that runs through the bottom of the boat, where these 2 shafts connect, there is a rather large "nut" that the shaft from the tranny runs through, it is less than a foot up from where the other shaft goes through the hull. This "nut" had water dripping from it and puddling in the bottom of the boat. The strange thing is, I was on the boat for 3 days and water continued to drip the whole time I was there, however the puddle didn't seem to get any larger. Does anyone know how I can stop the drip? One more question, my trannys say they are 1.91-1 reduction, does that mean if I take my engine RPM's and divide that by 1.91, that is how fast my props are spinning?
Thanks for any/all input

Steve