There is a depth of from somewhat over 10 feet of water, but this is limited to an effective depth of 3·10 metres where it passes over a small stream by a brick aqueduct. A line of steamers belonging to Messrs. Thomas & Co., of London, runs to Brussels regularly, and several Dutch lines of steam barges use this route. Sailing vessels and lighters are worked on the canal by means of the chain system, with _remorqueurs_, twenty to thirty being thus easily towed. The locks are large, and as many vessels pass at the same time, the trains are made up accordingly. When two meet, the ascending tug drops the chain, the train keeps on its right side, and the chain is again picked up by a grapple when the descending train has passed. With this system the vessels are easily steered by the men at the helm. When approaching a lock, the chain is thrown off in proper time, and the vessels’ way being checked, they gradually settle side by side in the lock. Great skill and care is used by the men, damage by collision rarely occurring. One great advantage attending this system of towage is that the tugs make no wash, which so much destroys the banks of canals. The tolls are light, and the rates for towage very low. Empty vessels only pay 20 c. for a _laissez passer vide_; this ticket, as in France, can be taken from any _bureau de navigation_ to any other place in the kingdom or in the Republic. Belgium has made a substantial contribution to the more important engineering features of canals by the construction of the La Louviére Canal lift on the Terneuzen Canal, which is illustrated on the opposite page. [Illustration: LA LOUVIÉRE CANAL LIFT.] This canal lift was constructed for the Belgian Government by the Société Cockerill, of Seraing, from the designs and under the superintendence of Messrs. Clark, Stanfield, and Clark, of Westminster, consulting engineers to the Government, and the patentees of the system. The difference between the levels of the upper and lower canals—that is, the height the boats are raised—is 50 feet 6¼ inches. The lift consists of two pontoons, or troughs, each 141 feet long by 19 feet broad, with 8 feet draught of water, and are capable of holding the largest size of barge that navigates on the Belgian broad-gauge canal system. Such barges are capable of taking 400 tons of coal or other cargo, so that the total weight of the trough, water, and barge is not much under 1000 tons. This immense weight is supported on the top of a single colossal hydraulic ram of 6 feet 6¾ inches diameter and 63 feet 9½ inches long, working in a press of cast iron, hooped continuously, for greater security, with weldless steel coils. The working pressure in this press is about 470 lbs. to the square inch. The time actually occupied in lifting or lowering is only two and a half minutes. The La Louviére lift is said to be the largest in the world.