It is curious to find that Mr. Nicholas Wood continued to object to the use of the steam-blast down even to the time when the Liverpool and Manchester Railway Bill was before Parliament. In his evidence before the Committee on that Bill in 1825, he said: "Those engines [at Killingworth] _puff very much, and the object is to get an increased draught in the chimney_. Now (by enlarging the flue-tube and giving it a double turn through the boiler) we have got a sufficiency of steam without it, and I have no doubt, by allowing the steam to exhaust itself in a reservoir, it would pass quietly into the chimney without that noise." In fact, Mr. Wood was still in favor of the arrangement adopted in the Wylam engine, by which the steam-blast had been got rid of altogether. If these statements, made in Mr. Wood's book, be correct--and they have never been disputed--they render it perfectly clear that George Stephenson invented and applied the steam-blast for the express purpose of quickening combustion in the furnace by increasing the draught in the chimney. Although urged by Wood to abandon the blast, Stephenson continued to hold by it as one of the vital powers of the locomotive engine. It is quite true that in the early engines, with only a double flue passing through the boiler, run as they were at low speeds, the blast was of comparatively less importance. It was only when the improved passenger engine, fitted with the multitubular boiler, was required to be run at high speeds that the full merits of the blast were brought out; and in detecting its essential uses in this respect, and sharpening it for the purpose of increasing its action, the sagacity of Timothy Hackworth, of Darlington, is entitled to due recognition. [Illustration: (Colliery Whimsey)] FOOTNOTES: [31] The same fallacy seems long to have held its ground in France; for M. Granier tells us that some time after the first of George Stephenson's locomotives had been placed on the Liverpool and Manchester line, a model of one was exhibited before the Academy. After it had been examined, a member of that learned body said, smiling, "Yes, this is all very ingenious, no doubt, but unfortunately the machine will never move. The wheels will turn round and round in the same place."