In 63 I sailed on the last sail rigged snapper smack on the Gulf of Mexico, an old 80 ft Mobile schooner left over from WWII when to sail, a commercial fishing boat had to actually sail because fuel was unavailable. Toilet facilities were either to stand at the rail somewhere aft of amidships or hang one’s posterior over the transom. The Peggy G had a large crew, eleven men. There were no women out there except rarely on one of the smaller diesel boats on which the captain’s wife went as cook and she shared the same facilities. There was no onboard equipment.
In nautical tradition the bathroom/toilet is referred to as, "the head". A sailboat is on course when it is pointing towards it's heading; ie; the pointy end, up front, generally going towards where you want to go.
The reason one should do ones business up front (rather than the back) is because the waves will wash the bow clean. If you poop off the, "poop deck" the nasty bits follow you for your whole voyage.