A Popular Exposition of the Effect of Forces Applied to Draught - new book

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: OPERATION OF HORSES UPON RAILWAYS. The draught of any power (P,) upon a level railway having been determined as = P X 200, it follows that, if the power of a horse under different circumstances be multiplied by that number, the product will exhibit his correspondent amount of draught, as is shown in the subjoined Table, founded upon the contents of Table II. TABLE IV. Operation of Horses on a Level Edge Railway. Time ot working in hours a day.Velocity in miles an hour.Draught in pounds.?144800 or 20 Tons.10222400 or 10 Tons.9314933-38411200758960667466-6576400485600394977-72104480 .1114072-6 123733-3If we contrast, with the contents of this Table, some accounts of the actual performance of horses, we shall see how very moderate are the former. Mr James Jessop, London, saw a horse drag, for a short time, by way of experiment, 27 tons on a level. On Lord Elgin's railway, each horse drags regularly 10 tons, besides waggons, which must be in all 12 tons on a level. On Sir J. Hope of Pinkie's railway, each horse is stated to draw 10 tons, at 4 miles an hour. This is wonderful; but I myself have seen an active and rather light horse drag about 7 tons at 4 miles an hour on a level, and was told that it was his usual draught and speed during 7 or 8 hours daily; say 13,680 Ibs. during 7 or 8 hours, at 4 miles an hour, while, by the Table, we have only 11,200 Ibs. during 8 hours, at 4 miles an hour. With the full load for a horse, weighing about 10 cwt. namely, 10 tons, I have seldom witnessed a greater working speed than about 2 miles an hour. It will thus be seen that the estimate of the average working draught of horses formed upon Mr N. Wood's observations, is, perhaps, as applied to Scotch draught horses at least, rather low than otherwise. I shall now give some example...