Page:Report from the Select Committee on Steam Carriages.pdf/211



Mr. John Macneil. 6 September, 1831. which the wheel would sink two or three inches; the section of the wheel is represented in the following sketch: The six-horse Waggons with their load, generally weigh four tons and a half; their wheels are six inches wide, and of a better description than the former, though sometimes one of their hoops projects beyond the other, as in the case of the nine-inch wheel; the four-horse Waggons, with their load, commonly weigh three tons and a half, their wheels are four-inches wide, and are more upright than the others, and have a more level bearing on the road; the farm Waggon, used in Northamptonshire, weighs on an average one ton one cwt., the breadth of a wheel is three inches, and it carries from one top to three tons, according to circumstances, and lasts nearly twenty years.

On an average line of road of not less than 100 miles, on which in many places materials of very inferior description must have been used, both in its formation and subsequent repair, what is the maximum weight per wheel (say if not less than four inches width of tire) which should be carried on any kind of Carriage (carriage weight included,) without risk of injury to the road?—On a road, such as here described, the injury will be considerable by any wheel passing over it; but without a more defined statement of the quantity and quality of the materials used. I do not think this question can be answered with any.degree of certainty; on all gravel roads however made, without a foundation or bottoming. I should say the weight on a four-inch wheel should not exceed fifteen cwt., and on a wheel less than that ten cwt, on the generality of roads, throughout the country: I do not think it would be safe to run a Carriage with almost any-width of wheel if the load much exceeded ten tons; in fact there are some bridges even between: London and Birmingham, that it would be running a risk to pass over with a Carriage weighing ten tons.

Can you from observation' day what proportion the breadth of the tire of wheels should be to the weight?—The breadth of tire, in proportion to the weight, will depend entirely upon the description of road over