Page:Report from the Select Committee on Steam Carriages.pdf/182



Mr. W. A. Summers. 19 August, 1831. Have you watched the operation of your propelling wheels on the roads?—Continually.

Have you ever seen the operation of a drag on a common coach going down hill?—Very frequently.

What is the effect produced on a road which is nearly dry?—The effect produced on a very hard road when nearly dry is very trifling, but on a soft or gravelly road it does great injury.

Does not it produce a glossy appearance on the rut?—Always.

Is that same effect produced by your Carriage in going down a hill?—No, certainly not, because our wheels in going down hill are always revolving.

By what operation do you decrease the velocity of the Carriage going down the bill so as to check the inclination of itself to run down the hill, and yet keep it under controul?—On arriving at the brow of the hill we throttle or wiredraw the Steam in order to check the velocity of the Engines, and if we find that the hill is so steep that the Carriage would run faster than we wish, we have two drags attached to the hind wheels, and with the foot we press on one drag or on both, as it may be required, and by that means regulate the velocity of the Carriage.

Does not that stop the motion of the wheel?—No, it does not prevent the wheel revolving.

How is the drag applied?—It is a kind of iron band or strap which goes round a portion of the tire of the wheel, and our power of breaking is multiplied by levers to a very great extent.

You have stated that the utmost weight your Carriage would carry, at the rate of ten miles an hour, was three tons; do you think you would be able to carry a much greater weight at the rate of five miles an hour only?—Certainly we should.

To what extent should you increase your power of carrying?—cannot answer that from experience.

At what period of slow motion do you think that the increased expence of fuel would be greater than the use of horses in draft?—I have not ascertained that from experiment; but I think Steam will