Inland students are usually not very convinced when shown the usual vector diagram of a boat sailing against the wind. They think of a boat keel as something to prevent capsizing rather than a device which provides an enormous lateral resistance and furnishes one of the vectors.An ordinary model boat in a tub of water is not satisfactory because it drifts around easily and will move erratically rather than on a given course. The solution to this problem is to run the boat on a tightly stretched wire six to eight feet long. The wire provides absolute resistance to lateral motion and is analagous to a keel, and yet the boat may realistically "heel" over as it travels up the wire against the blast of an electric fan.

No abstract