SMOKE PREVENTION.

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which is 4 feet in diameter, without friction. The space, G H, fig. 133, is 36 feetsquare. ■ .

The iron cone, which serves as a valve to the charging-drum or cylinder, is raisedand lowered by means of a chain passing round a worm-wheel, which is turned roundby an endless screw, acted upon by tlie long rod at c, which the workman can move byhand at pleasure, thereby lowering or raising the end of the short lever, d, to which thevalve cone is suspended. The cord by which the workman opens or shuts the airpiston-valve is seen at e, f. I have viewed with much pleasure the precise and easymovements of this feed-apparatus, at an excellent blast furnace in Codner Park ironworks.

SMOKE PREVENTION. Among the fifty several inventions which have beenpatented for effecting this purpose, with regard to steam-boiler and other large furnaces,very few are sufficiently economical or effective. The first person who investigated thissubject in a truly philosophical manner was Mr. Charles Wye Williams, managing directorof the Dublin and Liverpool Steam Navigation company, and he also has had the meritof constructing many furnaces both for marine and land stpam-engines, which thoroughlyprevent the production of smoke, with increased energy of combustion, and a more orless considerable saving of fuel, according to the care of the stoker. The specific inven-tion, for which he obtained a patent in 1840, consists in the introduction of a properquantity of atmospheric air to the bridges and flame-beds of the furnaces, through agreat number of small orifices, connected with a common pipe or canal, whose area canbe increased or diminished, according as the circumstances of complete combustion mayrequire, by means of an external valve. The operation of air thus entering in smalljets into the half-burned hydro-carburetted gases over the fires, and'in the first flue, istheir perfect oxygenation, the development of all the heat which that can produce, andthe entire prevention of smoke. One of the many ingenious methods in whichMr. Williams has carried out the principle of what he justly calls his Argand furnace,is represented in fig. 134, where a is the ash-pit of a steam boiler furnace; b, is the

mouth of a tube which admits the external air into the chamber or iron box of distri-bution, c, placed immediately.beyond the fire-bridge, g, and before the diffusion ormixing chamber,/. The front of the box is preforated either with round or oblongorifices, as shown in the two small figures e, e beneath fig. 134 ; / j s the fire-door,which may have its fire-brick lining also perforated. In some eases, the fire-door pro-jects in front, and it, as well as the sides and arched top of the fireplace, are constructedof perforated fire-tiles, enclosed in common brickwork, with an intermediate space, intowhich the air may be admitted in regulated quantity through a moveable valve in thedoor. I have seen a fireplace of this latter construction performing admirably, withoutsmoke, with an economy of one seventh of the coals formerly consumed in producing alike amount of steam from an ordinary furnace; h is the steam boiler.

Very ample evidence was presented last session to the Smoke Prevention committeeof the house of commons of the successful application of Mr. Williams’s patent inven-