SOAP 843 



furnace ; b is the mouth of a tube which admits the external air into the chamber or 

 iron box of distribution, c, placed immediately beyond the fire-bridge, g, and before 

 the diffusion or mixing chamber, /. The front of the box is perforated either with 

 round or oblong orifices, as shown in the two small figures e, e, beneath Jiff. 1854; d, 

 is the fire-door, which may have its fire-brick lining also perforated. In some cases, 

 the fire-door projects in front, and it, as well as the sides and arched top of the fire- 

 place, are constructed of perforated fire-tiles, enclosed in common brickwork, with an in- 

 termediate space, into which the air may be admitted in regulated quantity through a 

 moveable valve in the door. Fire-places of this latter construction perform admirably 

 without smoke, with an economy of one-seventh of the coals usually consumed in 

 producing a like amount of steam from an ordinary furnace ; h is the steam-boiler. 



Evidence was presented some years ago to the Smoke Prevention Committee of the 

 House of Commons of the successful application of Mr. Williams's patent invention to 

 many furnaces of the largest dimensions, more especially by Mr. Henry Houldsworth, 

 of Manchester, who, mounting in the first flue a pyrometrical rod, which acted on an 

 external dial-index, succeeded in observing every variation of temperature produced 

 by varying the introduction of the air-jets into the mass of ignited gases passing out of 

 the furnace. He thereby appeared to demonstrate, that 20 per cent, more heat could 

 be obtained from the fuel, when Mr. Williams's plan was in operation than when the 

 fire was left to burn in the usual way, and with the production of the usual volumes 

 of smoke. 



It should be borne in mind that consumption of smoke implies cleanliness, economy 

 of health, and economy of labour. Are not these sufficient reasons to induce manufac- 

 turers to use the best means possible to do away with a great nuisance, and to avoid 

 the waste of so precious a commodity as coal, for a time may come when we shall 

 have cause to regret our extravagant consumption of that article? We have shown 

 that the cause of smoke is incomplete combustion, caused either by the want of a 

 sufficient quantity of air, or by such air being admitted under such circiimstances that 

 its admission is worse than useless. Experience has proved that there are but few 

 difficulties in constructing arrangements which will effect the consumption of smoke ; 

 but desirable as the process is, it must be admitted that smoke -consuming is not 

 found to be economical, although it is in every sense desirable. 



By means of Wright's patent smoke-consumer, the air admitted into the furnace 

 is regulated by a self-acting ventilating door, so as to furnish the necessary amount 

 of oxygen requisite for perfect combustion. The air is also diffused over the entire 

 surface of the fire. By this apparatus, a partially-decomposed and nearly red-hot 

 jet of steam is projected from over the door down upon the incandescent fuel. 

 By that means the fire becomes brighter, not damped, as it would be were wet steam 

 used, and not only causes a vacuum in the furnace, thereby increasing the draught, 

 but effectually prevents the cold air admitted through the door and the gases distilled 

 from the coal from touching the boiler-plates, thus avoiding 



1. The cooling of the boiler-plates by the action of the cold air striking them, and 

 causing the continual expansion and contraction of the metal, which is so injurious 

 to boilers. 



2. The gases formed by the first action of the hot furnace on the coal thrown in 

 from coming in contact with the top of the furnace or boiler-plates, the temperature 

 of which being no greater than that of the contents of the boiler, can only cool those- 

 gases to such an extent that their combination with oxygen cannot take place. 



Not only are these two great evils avoided, but the jet of steam forces the gases 

 distilled from the coal on to the incandescent fuel at the back of the furnace, 

 together with the air admitted through the door, thus multiplying the points of contact 

 ad infinitum, thereby causing instantaneous combination of their elements, making 

 the combustion as perfect as it can.be in a manufacturing point of view; and ob- 

 taining all the heat that the combination of oxygen with the hydrogen and carbon 

 can give. The smoke is never allowed to pass the bridge of the furnace ; in fact, its 

 forming is prevented. The apparatus is simple and efficient in its action, not liable 

 to get out of repair. It can be applied in two days at the utmost, and has been fre- 

 quently fitted in one day, and it is adapted for every description of furnace. Under 

 all circumstances, however, it has been proved that careful stoking is the best method 

 for preventing the escape of smoke. 



SIVXOKY QUARTZ. A variety of quartz having a smoke-coloured tint : it com- 

 prises the clove-brown variety of cairngorms. 



SOAP is a chemical compound, manufactured on a very extensive scale, forming, 

 accordingly, a considerable article of commerce. It is a compound resulting from the 

 combjnatiou of certain constituents derived from fats, oils, grease of various kinds, 

 both animal and vegetable, with certain salifiable bases, which, in detergent soaps, 

 are potash or soda. 



