I enjoyed reading your essay, as usual. You may have researched much of Europe's early sea travel of fourteen hundreds, but there is now evidence that the stories of Vikings visiting N. America are very likely true with townships found in Newfoundland. The Irish and Scottish Hebridian fisherman have many legends of having been washed up on western lands among the longshoremen men of an earlier time. The Welsh legend of a leather coracle being taken across to America and returning, is, or could be most pre-christian, and told by scribe monks to later Sanctify a Columban bishop of the pre-RC Celtic church. I personally would not wish to travel far in a coracle, but a lifeboat of canvas make has been known to travel thousands of miles in Atlantic conditions. In modern, relatively, times an armada of small boats crossed the narrows of the North Sea from East Anglia to Dunkirk and returned, many overladen. That sea was not as rough as the Atlantic might be, but other voyages have since been filmed, of two men rowing the Atlantic, or a small longship crossing the northern North sea. Take a gander at the size of the ship, in dock in the Thames, that took Sir Frances Drake to San Francisco Bay 60 yrs later, and was careened in Indonesia before coming home around Africa. Not something you would head out across an ocean in today!