Head (watercraft)

The name derives from sailing ships in which the toilet area for the regular sailors was placed at the head or bow of the vessel.

In sailing ships, the toilet was placed in the bow somewhat above the water line with vents or slots cut near the floor level allowing normal wave action to wash out the facility.

The Journal of Aaron Thomas aboard HMS Lapwing in the Caribbean Sea in the 1790s records that a canvas tube was attached, presumably by the ship's sailmaker, to a superstructure beside the bowsprit near the figurehead, ending just above the normal waterline.

Submarine heads face the problem that at greater depths higher water pressure makes it harder to pump the waste out through the hull.

As a result, early systems could be complicated, with the head fitted to the United States Navy S-class submarine being described as almost taking an engineer to operate.

The head on the beakhead of the 17th-century warship Vasa . The toilets are the two square box-like structures on either side of the bowsprit . On the starboard side, there are still minor remnants of the original seat.