CANALS AND RAIL-ROADS.

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sufficient accuracy, the weights which a horsewill drag in a boat upon a canal, I shall beobliged to have recourse to the reports ofthose engineers whose practice in that linehas enabled them to obtain the necessary data.

Mr. R. Stevenson, of Edinburgh , in hisreport on the Edinburgh Rail-way, in 1818,states, “ Upon the canals in England, a boat of30 tons burden is generally tracked by onehorse, and navigated by two men and a boy ;on a level Rail-way it may be concluded that agood horse, managed by a man or lad, willwork with eight tons ; at this rate, the workperformed on a Rail-way by one man and ahorse is more than in proportion of one-third ofthe work done upon the canal by three personsand a horse and Mr. Stevenson, in his calcu-lations afterwards, assumes the power of ahorse, upon a good Rail-way, equal to 10 tons.

Mr. Sylvester, in his report on the Liverpooland Manchester Rail-way, gives 20 tons as theperformance of a horse upon a canal, travellingat the rate of two miles an hour.

The variation between these' two statementsmay have arisen from the observations beingmade on canals of different widths. Mr. Ste-venson, in another report, states, that thestriking difference between the draught othorses, on coming out of a narrow canal, into a