The “river steamer,” as the stern-wheel shallow draught vessels on Canadian waters are called, is a boat of peculiar construction. Three things are absolutely necessary. First, a perfectly smooth bottom; second, an absence of rigidity in the hull and motive-power; third, a propelling-power on the surface of the water—three points, apparently easy of accomplishment, but in reality very difficult, and which to understand requires long practice with the steamers, and their uses. Indeed, no inconsiderable portion of a captain’s or pilot’s life has passed before he has learned the “handling”; but when once the lesson has been learned, it is wonderful what can be done with these wheelbarrow steamers.
Mr. Shelford[303] holds that these are by far the most useful class of boats employed on the canals of Canada. The absence of a keel or any such obstruction enables the boat to be turned like a dish on the water; while the four rudders (sometimes 20 feet long) will guide her with a nicety in rapids and currents where an ordinary steamer would be helpless. The absence of rigidity in the hull and machinery enables the steamer to be driven ashore on any soft bank, the cargo discharged or loaded, and the boat without difficulty backed off.
The propelling power is a large diameter wheel at the stern of the boat, the full width of the vessel, resembling the undershot wheel of a mill, and driven by two cylinders, one on either side. The floats of this wheel are but 8 to 10 inches in the water when light, and 30 inches when loaded, and do not therefore produce those destructive currents which come from the screw or paddle steamer.
The boats which are used on the rivers of the north-west of Canada are about 220 feet, 38 to 40 feet beam, and 10 to 12 inches draught when light, and carry themselves about 400 tons, and will push (not tow) three times as much more on barges built like the steamers.
Perhaps the most efficient system of canal boats and of canal transport generally known in the United Kingdom is that adopted on the Aire and Calder Canal. Steamers are employed to tow a fleet of canal boats or barges, varying from ten to twenty in number, each carrying about 40 nett tons of traffic. The locks, which are 215 feet in length, take the steamer, tender, and eleven boats all at one time; but if there is a longer train of boats, it has to be broken in two. The boats are 20 feet long, 16 feet wide, and 7 feet or 7 feet 6 inches deep. When loaded, they draw from 6 feet to 6 feet 6 inches of water, and the whole train carries from 700 to 900 tons. Usually, instead of towing these boats, they are pushed from behind, which offers an advantage in the steering. The steamer has two direct-acting cylinders—one on each side, and a wire rope is carried round a pulley direct to them, being afterwards threaded through guides attached to each boat. The steering arrangements are so contrived that the train can go to any curve by the two convex surfaces, and yet it is free to rise and fall vertically. The boats are coupled together by wire ropes, which run alongside the whole of the boats through guides at each corner of each boat. The ropes are then passed over the steering wheel upon the steamer. The boats are really iron boxes, which, when traffic is carried, say from Leeds to Goole for shipment, are placed in a hoist, inside which there is a cage with a cradle, in which the boat is secured. When the boat has been raised to the height of the shoot it turns over automatically and discharges the coal or other cargo into the ship through the shoot or spout employed for that purpose. The boat and cradle, having resumed their original position, are then lowered back again to the canal-level by the same hydraulic arrangement employed to raise them. Mr. Bartholomew, the Manager of the Aire and Calder Canal, has stated[304] that the cost of mineral transport by this system, including the return empties, was only 0·0119d. per ton per mile; the cost of tugs carrying general cargo and merchandise being ·034d. per ton per mile; whereas the cost of the same traffic on the Leeds and Liverpool Canal, where similar facilities do not exist, would be ·30d. per ton per mile. The difference of cost is mainly due to the difference in the number of men employed. Usually, two men are employed on each boat, and four men are employed for tugging, making 28 men in all for 12 boats, whereas a train of boats can be worked by the system described by the tug crew of four men only. The Aire and Calder Company have now arranged their boats in such a way that they may carry general merchandise as well as minerals, having fitted them with decks and hatchways for that purpose.
Mr. E. J. Lloyd submitted to the Select Committee on Canals (1889) a statement showing the size of the craft that the various canals of England and Wales were capable of carrying.[305] The figures are instructive, and are worth perusal by any one interested in the subject. It showed that there are very few cases in which the existing navigations can carry craft over 100 feet in length. The most usual dimensions are 70 or 75 feet by 12 or 14 feet width. The Aire and Calder Canal, which takes boats of 212 feet by 22 feet, is a notable exception to the general rule. Boats of 163 feet by 29 feet 6 inches can also travel on the Gloucester and Birmingham Navigation, while the Severn can take craft of 270 feet by 35 feet, and the Thames, from London Bridge, can carry vessels of 140 feet by 22 feet. Again, on part of the Kennett and Avon Canal, craft of 120 feet by 18 feet can be navigated. Mr. Lloyd, who has had a great deal of experience in canal navigation, has proposed the adoption of improved locks on the leading English canals capable of taking boats 110 feet long, 11½ feet wide, and 6 feet draught, the carrying capacity being about 120 tons.[306] Mr. Abernethy has proposed that the canal boats should be capable of carrying 200 tons, and the canals adapted thereto;[307] while Sir James Allport has contended that for facility of handling traffic small boats are better than large ones, and should be preferred accordingly.[308]
In India, steamers have been placed by Government on the Sone canals, and will continue to run until the task is taken up by private enterprise, as is now being done on the Orissa canals.
The following is a description of one of them named the Koel:—
| Length | 114 | feet |
| Beam over all | 16½ | ” |
| Draught, full loads | 3½ | ” |
| Coal bunker capacity | 7 | tons |
Of which 5¾ tons are used on the trip between the head of the canal and Arrah and back, being a run of 116 miles, occupying about 26 hours, or at the rate of 7·450 lbs. per hour, a very large consumption for an engine of 25 nominal H.P.