twice the size of the Suez Canal at the surface, which is 100 meters, or about 320 ft., while it is only about 75 ft. at the bottom; the Amsterdam Canal is 78 ft. wide. The new Manchester Canal is to be 100 ft. of full depth, and it boasts of this superiority over the great work of Lesseps. The figures given above will show how far short it comes of the dimensions of the St. Petersburg Canal. The Manchester Canal is to be 24 ft. in depth; in that it has the advantage of 2 ft. more than the St. Petersburg Canal; but with the ample width this one possesses, this, or even a greater depth, can be given if it should be found necessary. Most probably this will have ultimately to be done, for ocean going steamers are rapidly increasing in size since the St. Petersburg Canal was planned, and in a very few years the larger class of steamers might have to deliver their cargoes at Cronstadt, as before, if the waterway to St. Petersburg be not adapted to their growing dimensions. [Illustration: THE ST. PETERSBURG AND CRONSTADT MARITIME CANAL, OPENED BY THE EMPEROR OF RUSSIA, ON WEDNESDAY, MAY 27, 1885.] "The dredging between the embankments of the canal was done by an improved process, which may interest those connected with such works. It may be remembered that the Suez Canal was mostly made by dredging, and that the dredgers had attached to them what the French called 'long couloirs' or spouts, into which water was pumped, and by this means the stuff brought up by the dredgers was carried to the sides of the canal, and there deposited. The great width of the St. Petersburg Canal was too much for the long couloirs, hence some other plan had to be found. The plan adopted was that invented by Mr. James Burt, and which had been used with the greatest success on the New Amsterdam Canal. Instead of the couloir, floating pipes, made of wood, are in this system employed; the earth or mud brought up has a copious stream of water poured on it, which mixes in the process of descending, and the whole becomes a thick liquid. This, by means of a centrifugal pump, is propelled through the floating pipes to any point required, where it can be deposited. The couloir can only run the output a comparatively short distance, while this system can send it a quarter of a mile, or even further, if necessary. Its power is not limited to the level surface of the water. I saw on my visit to the canal one of the dredgers at work, and the floating pipes lay on the water like a veritable sea-serpent, extending to a long distance where the stuff had to be carried. At that point the pipe emerged from the water, and what looked very much like a vertebra or two of the serpent crossed the embankment, went down the other side, and there the muddy deposit was pouring out in a steady flow. Mr. Burt pointed out to me one part of the works where his pump had sent the stuff nearly half a mile away, and over undulating ground. This system will not suit all soils.