Report from the Select Committee on Steam Carriages/Telford
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 and horses were four tons travelling at equal velocity and with equal breadth of tire, which do you think would do the least injury to the road?—I should think that the Steam Carriage would do the least injury, but that is not from experience of Steam Carriages, but only from my general information, always taking for granted that there is no projection outside the wheel.
If under those circumstances, the breadth of the tire of the Carriages drawn by horses, were two inches and a half, the usual breadth, and the breadth of the tire of the Steam Coach were four inches, should you then have any doubt which would do the least injury to the road?—I have already said if the tires were equal I conceive the Steam Carriage would do the least injury, and certainly the chance of injury will be lessened if the tire is made double the breadth.
If the breadth of the tire of the wheels of Steam Carriages could be extended to six inches, might they not in many states of the roads be rather beneficial than injurious?—Where the road is properly made of good materials and well consolidated, the mere pressure of a Carriage would not have any effect.
Do you think it would be fair to impose an equal toll, weight for weight, on Steam Carriages and on Carriages drawn by horses?—I think it ought not to exceed that.
Do you think that it ought to be equal, as the one Carriage you state does not do so much injury as the other?—In justice it ought to be diminished, but that is only opinion until it is proved.
Have you paid any attention to the mode of charging toll on Steam Carriages?—I have not.