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its carrying capacity was reduced by the weight of the machinery. Two other boats were built about the same time, which were provided with double, or twin screws, but they were also unsuccessful, and for the reason already stated.

In 1860, a system of chain haulage was experimented with and proved a perfect failure.

The most successful effort was made about eight years ago. It consisted in the introduction of small steam-tugs, which were placed upon a level 25 miles long, for towing boats in trains. These tugs were 60 feet long and 7 feet beam; were fitted with powerful machinery, and were able to tow five boats, carrying 40 tons each, or an aggregate of 200 tons. They were able to tow a train of three boats, carrying an aggregate of 120 tons, at a speed of 24 miles per hour, with a slip of about 50 per cent. The boats. of this canal are 60 feet long, 13 feet wide and draw four feet when carrying 40 tons. In 1866, horses had been withdrawn from the level referred to, and the towing was done exclusively by two of these steamers.

Upon the Shannon, steamers 72 feet long, 13 feet 3 inches beam, drawing 4 feet 8 inches of water, and carrying 50 tons of cargo, have been successfully introduced.

The small size of this canal, and the limited carrying capacity of its boats, would seem to preclude the successful general introduction of steam upon it, in cargo-carrying boats, or for towing purposes, where locks occur at short intervals.

Forth and Clyde Navigation.

The Forth and Clyde canal extends from Grangemouth on the Forth, to Bowling on the Clyde, a distance of 35 miles. From a point about 26 miles from Grangemouth, a branch 4 miles in length leads to Glasgow, where it connects with the Monkland canal, leading from Glasgow, 12 miles, to Woodhall. On the Forth and Clyde, in 35 miles, there are 40 locks, at intervals varying from 50 yards to 17 miles, while on the Monkland there are 10 locks in a distance of 12 miles.

The capacity of the horse-boats used on the Monkland canal is about 60 tons, and the movement is nearly all in one direction, the boats returning light. The cost of transporting 60 tons ten miles, for towing and for the crew, including the return of the empty boat, was, in 1859, about 9 pence per boat mile for the round trip, which is at the rate of about 24 mills per ton mile.

For a round trip of 80 miles, made up of 10 miles on the Monk

land canal and 30 miles on the Forth and Clyde and return, the cost per boat mile was about 11ğ pence, or at the rate of 3 mills per ton mile.

Efforts to introduce steam upon this line date back as far as 1789, when Symington designed and built steamers for that purpose. Again, in 1801, the "Charlotte Dundas " was built and tried; and at intervals since that time experiments have been made, all of which, however, resulted unsatisfactorily.

In the year 1856, a steamer designed by Mr. James Milne, of the Forth and Clyde navigation, was built and put in operation. This steamer, which had been a horse-boat, carrying 80 tons, had two 6 inch cylinders, with ten inches stroke of piston. The boiler was upright, tubular, 3 feet in diameter, and weighed, together with the engines and water, 2 tons. With 35 pounds of steam, the boat was propelled, loaded, at a speed of 4 to 5 miles per hour. From the date of their completion, in 1856, to 1866, a period of ten years, the engines had been constantly at work, and were still (1866) working most satisfactorily, but little repair and no renewals having been needed either for boiler or engines. The boiler was intended to carry 100 pounds pressure, and the surplus power was designed to be employed in towing, but the traffic not requiring it, the boat had not been so used. Mr. Milne objected to towing, on account of the delay which must occur at the numerous locks.

Mr. Milne said, "The application of steam power to this boat having proved successful, engines were designed and fitted to the luggage boat Marjory,' carrying 35 tons; to one of the canal ice-breakers; to masted lighters for canal and coasting trade, carrying 120 tons; and designs for a scow or mineral barge, carrying 60 tons, on the Monkland canal, and 75 tons, on the Forth and Clyde canal, all of which proved successful, and had been the precursors of about 70 canal steamers now (1866) at work on the canal, and from the canal to the contiguous sea-coasts."

The rate of increase in the number of steamers on these canals is indicated in the following table:

The costs of transportation by horse and steam power appear to have

showing a saving of about 43 per cent. In each the return trip light.

case the boat made

As to the saving in time, it is said that on trips of average distance, as 30 or 40 miles and return, the steamers make three trips while the horse-boat makes two; on longer trips, the saving would obviously be greater.

Regent's Canal.

On this canal the sectional area of the waterway, as compared with that of the boats navigating it, is about as 4 to 1. The average weight of the boats or barges is taken at 15 tons, and the average cargo at about 55 tons.

In the year 1854 the canal company issued an advertisement offering a premium of £100 for the best, and of £50 for the second best tug-boat which should be put in competition by a certain day. The premium was awarded in August, 1855, to Mr. Inshaw, of Birming ham, for the screw tug-boat "Birmingham," which was purchased by the company, and which was, until 1865, constantly employed in towing barges upon the summit level of the canal. This tug-boat was 70 feet 8 inches long, 6 feet 8 inches beam, and drew 34 feet of water. It was fitted with a multitubular boiler and an engine having a pair of 7-inch cylinders, which was operated with steam of 60 to 70 pounds pressure. Two screws, having a pitch of 4 feet, were placed near the stern, and revolved in opposite directions by means of bevel wheels geared two to one. The capacity of this tug may be understood from the following performance, made June 15th, 1862. Between the hours of 6.15 A. M., and 7.45 P. M., a train of 20 barges, 17 of which were laden with an aggregate of 931 tons, was towed a distance of 11 miles. The cost of working this tug for the 8 months ending May 31st, 1865, was £344 28. The distance steamed was 3,519 miles; number of barges hauled 2,023; the gross amount of cargo conveyed was 59,738 tons. The cost, per train mile, for labor, repairs and fuel was 1.96 of a shilling (33 cents). The cost per ton mile for the same items was 1.383 of a penny (2 cents). In each case the cost of fuel was, and that of labor and repairs of the entire cost. The coal consumption is said to have been rather large, on account of insufficient boiler capacity.

The opinion was expressed that steam could not be economically employed on the Regent's canal by the canal traders, unless some plan were adopted for combining the tug with the cargo vessel, so that they might pass through the locks together, and be readily separated at the end of the journey. In accordance with this view, Mr. Thomas, in 1859, in a report to the canal company, recommended that the boats be constructed in two parts; the total length not to exceed the length of the boats then in use. It was proposed that the part containing the machinery and rudder should be as short as it might be practicable to have it, and should form the after part of the combination. This should be made to connect with the fore, or cargo-carrying part of the boat, in such a manner that the two would form a perfectly continuous and complete steamer. The principal advantage which it was claimed would be derived from this plan would result from the possi bility of keeping the steam power constantly at work, and from the fact that the necessity of fitting steam power permanently to each boat would be obviated.

The River Severn.

This river, which is in some places narrow and tortuous, has been rendered navigable by the construction of dams and locks. The boats trading upon it carry 30 to 40 tons and draw about 3 feet of water Steam tugs were introduced about the year 1856. Those first used had engines of 30 to 40 horse-power, and were propelled by reefing paddle-wheels. These boats answered very well; they towed trains of as many as twelve boats, carrying cargoes of 30 tons each, at speeds of from 2 to 3 miles per hour, against a current of 2 miles per hour. In order to avoid the detentions at the locks, the plan has been adopted of constructing large basins in connection with them. These basins are each provided with a pair of gates, and thus permit the passage of an entire tow at a single lockage. Tows are thus locked through very expeditiously.

Since the introduction of these tugs, boats of a different description have been employed and have been found to work still more satisfactorily. These are barges 70 feet long, 12 feet beam, and drawing 3 feet of water; they are each fitted with a pair of direct-acting engines, with cylinders 7 inches in diameter and 9 inches stroke of piston. Twin screws 2 feet 6 inches in diameter are used. The boats thus fitted are able to carry 40 tons of cargo, and at the same time to tow two boats carrying 30 tons each. The steamer with a single boat in tow, together carrying 70 tons, can make 24 miles per hour against

a current 3 to 4 miles per hour. This is considered the most economical mode of steam towing on the Severn. One hundred tons has been moved, with a consumption of from 67 to 85 pounds of coal per mile.

Ashby-de-la-Zouch Canal.

Upon this canal there is a large coal traffic, and as there is a 30mile level over which this traffic passes, the coal owners proposed, some years since, to employ steam power for towing purposes, and with that view ordered a tug from Mr. Inshaw, the successful competitor upon the Regent's canal. The Midland Railway Company, however, who were the proprietors of the canal, refused to allow the boats to be used, on the ground that it would cause injury to the banks.

Proceedings were instituted in chancery, and for the purpose of obtaining information as to the effect which would be produced, Mr. Pole was directed, as engineer, to conduct experiments with the boat which had been provided. These experiments were made in the month of May, 1859, with the tug, which was of the size ordinarily used on the canal, to wit: 70 feet long, 7 feet wide, 4 feet deep. It was fitted with engines of 6 horse-power (nominal?), working twin screws at the stern. The experiments comprised a variety of conditions, as to the load of the steamer and as to the number of boats towed, and the speeds attained varied from 1 to 5 miles per hour.

The results of the experiments are thus stated by Mr. Pole: "Up to a speed of 3 miles per hour no wave of injurious character appeared. Between 3 and 34 miles per hour, a breaking wave appeared occasionally, in curves and shallows. Above 3 miles per hour, the breaking wave became continuous and took a more marked character. At 4 miles per hour the injurious character of the wave became very decided. At 5 miles per hour, even in a much enlarged section, the wave was still more increased, breaking sometimes over the tow-path, and being followed by other waves in succession." "It was a very decided result of these experiments that the twin screw did not, of itself, at any speed attained, give rise to any wave or surge at all injurious to the banks of the canal."

Mr. Pole, as the result of his experiments, was led to recommend the admission of steamboats upon the canal, with such a limitation of their speed as would avoid the production of an injurious wave. Steamers were admitted upon the canal in accordance with this recommendation.

[Senate No. 71.] 9