Page:Report from the Select Committee on Steam Carriages.pdf/138



Mr. Richard Trevithick. 12 August, 1831. You think that the Steam Engines already prepared the home would go on the common roads?—They are between sinking and swimming at present, and I think they will swim; I think that the improvement is effected, and that they will do.

Would it not lighten the weight of Engines if you had fixed stationary Engines to pump gas, fifty atmospheres for instance; and shift the vessel containing it at each stage?—We do not want air or gas.

Something that has a power to drive?—A vessel that weighed that would be so heavy, it would not carry its own weight; the vessel it was compressed into would be of very considerable weight; a cubic inch of water will fill a cubic foot.

In the application of your power to a Steam Carriage, do you suppose there would be less danger of bursting than at present exists?—Yes; this cannot burst; that is prevented.

Have the goodness to state your reason?—There are five separate cylinders, the one encircled in the other; and if the boiler, or the inner circle burst, there are four other circles that might take the pressure, one after the other, before it can externally explode, which outer circles are never heated; and the boiler can never be heated or low, because the steam that is made use of by the Engines is returned every stroke into the boiler, and provided an Engine is tight, may work for ever without a fresh supply of water.

What height would the shaft be, as applied to your Steam Carriage?—It does not require to be higher than a common Steam Carriage.

Have the Steam Carriages that now ply on the roads a shaft?—No; they get their fuel through a fire door, but it will answer best to fill through you get considerable advantage. In the first place, you have a less boiler; by having a less boiler it is lighter; it is much stronger by getting a greater pressure; there is 75 per cent, of the fuel; if you take the average of the advantages, it will save daily nearly ten to one on travelling Engines.

That will render it necessary to have a chimney in