Gary
A summary from Encyclopedia Britannica online(see below for http location)
"lateen sail, triangular sail that was of
decisive importance (emphasis mine, hjh) to medieval navigation. The ancient square sail permitted sailing only before the wind; the lateen was the earliest fore-and-aft sail. The triangular sail was affixed to a long yard or crossbar, mounted at its middle to the top of the mast and angled to extend aft far above the mast and forward down nearly to the deck. The sail, its free corner secured near the stern, was capable of taking the wind on either side, and, by enabling the vessel to
tack into the wind, the lateen immensely increased the potential of the sailing ship.(emphasis mine, hjh)The lateen is believed to have been used in the eastern Mediterranean as early as the 2nd century ce, possibly imported from Egypt or the Persian Gulf. Its effective use by the Arabs caused its rapid spread throughout the Mediterranean, contributing significantly to the resurgence of medieval commerce. Combined with the square sail, it produced the ocean-conquering full-rigged ship. The Sunfish class of one-design sailboats is lateen gged."
http://www.britannica.com/EBchecked/topic/331395/lateen-sail - 83k - Cached - Similar pages
On a canoeing/fishing trip on Lake Isabel in the Quetico, I fabricated a hasty lateen sail and mounted it on a mast and attached it to my smooth-bottomed 17 foot Sears-Roebuck canoe. We, (me, my son, and his friend, they were 14 at the time) then "sailed" up the lake with the wind, then came back to camp tacking against the wind. Great fun but a lot of bailing cause of the lean of the canoe as we tacked into the wind. I can see where a keel, even a small one like the one on a Grumman canoe, would have helped resist the leaning.
Hey, this is fun, almost like Dr Seuss and Oh, the places you'll go and the things you'll see!