such an advance on former instances that it was considered a bold experiment. The Morris Canal between the Hudson and Delaware "is peculiar," wrote the British engineer Stevenson, in 1837, "as being the only canal in America in which the boats are moved from different levels by means of inclined planes instead of locks. The whole rise and fall on the Morris Canal is 1557 feet, of which 223 feet are overcome by locks, and the remaining 1334 feet by means of twenty-three inclined planes, having an average lift of 58 feet each. . . The car [on which canal boats ascend and descend] . . consists of a strongly made wooden crib or cradle . . on which the boat rests, supported on two iron waggons running on four wheels. When the car is wholly supported on the inclined plane, or is resting on the level, the four axles of the waggons are all in the same plane . . ; but when one of the wagons rests on the inclined plane, and the other on the level surface, their axles no longer remain in the same plane, and their change of position produces a tendency to rock the cradle, and the boat which it sup-
