17 August, 1831.
constructing weighs two tons without water, it is made stronger because there are not any practical data yet respecting the parts.
Veneris, 19° die Augusti, 1831.
Thomas Telford. Esquire, called in; and Examined.
You are aware that the object of this Committee is to ascertain, as far as practicable, how far the operation of Carriages propelled by Steam upon public roads is more or less injurious than the operation of Carriages drawn by horses?—I have never had any experience of Steam Carriages upon roads, and therefore I cannot say experimentally what effect they will produce, but if there is no projection upon the surface of the wheel and they are not suffered to drag upon the road, it does not appear to me that any injury can arise more, but rather less than by common Carriages.
Do you consider that supposing the weight of a Steam Carriage were equal to that of a Carriage drawn by horses, that is two tons each, the injury done to the road by horses or by the Carriage would be the greatest?—I should expect that by the horses.
In a much greater degree, do you conceive?—I cannot exactly say the proportion, but I should think the greatest degree of injury arises from the horses' feet.
What is the nature of the injury done to roads by the travelling of Carriages and horses?—By the horses chiefly by tearing up the surface with their shoes; I do not consider that the pressure of the wheels upon a good made road is nearly so injurious to the road as the tearing up of the road by the horses' feet.
Supposing that the operation of a Steam Carriage were so perfect that there should be no sliding of the wheels, and that such Steam Carriage were of four tons weight, and also that the joint weight of a coach
