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in the chimney, to give sufficient intensity tothe fire. To effect a greater rapidity, or toincrease the draught of the chimney, Mr.Stevenson thought that by causing the steamto escape into the chimney through a pipewith its end turned upwards, the velocity ofthe current would be accelerated, and such wasthe effect; but, in remedying one evil, anotherhas been produced, which, though objection-able in some places, was not considered asobjectionable on a private Rail-road ; the tubethrough the boiler having been increased, thereis now no longer any occasion for the actionof the steam to assist the motion of the heatedair in the chimney. The steam thrown in thismanner into the chimney acts as a trumpet,and certainly makes a very disagreeablenoise; nothing, however, is more easy toremedy, and the very act of remedying thisdefect, will also be the means of economisingthe fuel.
I have before said, that economy of fuel hasnot been an object where those engines havehitherto been used; no attempt has, therefore,been made to lessen it; and the steam, afterperforming its effect in the cylinders, has beenallowed to escape into the atmosphere. Thewater with which the engine is supplied, hasgenerally been heated in a vessel by the sideof the road, and carried in a barrel, from which