Page:Report from the Select Committee on Steam Carriages.pdf/185



Mr. W. A. Summers. 19 August, 1831. there is a noise, but it is so trifling that the rattling of the wheels on the road entirely drown it.

Is there continually steam being let off from the safety valves?—Almost continually.

Does that produce any disagreeable effect to the passengers?—None whatever; all the waste steam is blown into the furnace, which entirely prevents any noise that can be beard on the road.

İt has been stated to the Committee, that in some Steam Carriages actually in operation, there is a very peculiar noise from the escape of the steam, from whence does that proceed?—It proceeds in one Carriage, which I have seen running along the roads, from the steam being blown in at the bottom part of the chimney of the furnace, at a distance very near to the open air.

That may be obviated by a different form of chimney, may it not?—No doubt it may.

You are aware that that principle is one of the most important principles which has been introduced into the working by steam?—I am quite aware, that on the Liverpool and Manchester Railway that is the principle they have adopted with some success. We have produced the same effect by another, and I think better means.

Will you state by what means you produce that effect?—Instead of blowing our waste steam into the chimney, in order to produce a draught, we have a fan or blowing machine, which is driven by the Engines when in operation, and this gives us intensity of heat in the furnace. The waste steam from our Engines goes into a double casing round the furnace; we admit a small portion underneath the fire-bars of the grate, and the remainder is allowed to expand itself into the double casing, after which it comes over the top of the fire, and escapes in the form of invisible vapour.

Then in fact you arrive at the same result, but with this difference, that you increase the draught of the fire by using a certain quantity of the power of your engine, whilst those who introduce the steam into the chimney increase the draught by a power