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end towards the Mediterranean. Thus the French en­gineers proposed to preserve the level of the water in their canal at Has el Moyeh equal to the low-water level at Suez, and to throw all the remainder of the fall 26*64 English feet on the remaining distance of thirty English miles; and by so doing they conceived that energy would be given to the current of the canal to clear its bed from drift sand, and to hollow out and maintain a channel in the shallow muddy bottom of the bay, so as to afford a reasonable depth of water in the port of Tineh. But it may be doubted if so great a velocity is wanted; and if applied, whether it would be likely to effect the object; because, when a stream of water descends on an inclined plain with a great velocity, and meets a level surface on entering the bed of its recipient sea, its current will naturally be reflected upwards with a force and direction in some ratio to its velocity of descent, and the formation of sand banks and bars is the natural result of the union taking place with too great a declivity or velocity; or, in other words, there is maximum of velocity for the useful scour of the mouth of a river entering a lake or sea; and I should prefer obtaining a great momentum with a velocity of current not exceeding two and a half miles per hour.

It now only remains to give some approximate estimate of the cost of such an undertaking.

The French engineers calculating on restoring the an­cient canal from Suez to Bubastes, and of adding a branch from Serapeum to Tineh, estimated the expense at only £691,000, the length of the two works being 117 miles, and the depth 18 feet, to take vessels drawing 15 feet, and containing six or seven locks.

The section of the French project of canal is smaller than that now proposed (viz. 21 feet deep); I nevertheless consider the estimate as too low.