Well, originally the milk came from sea cows but they were found some of the guys got romantically involved, especially if they'd been at sea for some time. Whalers used to use whale milk, making the new guys in the crew go overboard with a bucket to milk the whales whenever the ships crossed the equator or found a lactating whale. Dolphins were used but to no porpoise as their milk was found to upset the stomachs of certain ship's captains. Goats were tried, as were sheep and llamas, but they really aren't sea-going animals and they again caused certain problems with the crew after months at sea.

So cow's milk it was! "Let the farm boys handle their own romantic entanglements," one salty old skipper said. "We've got enough problems with our cabin boys."