General Notices. 451 



MISCELLANEOUS INTELLIGENCE. 



Art, I. General Notices. 



Consuming the Smoke of Hothouse Furnaces. — The injury done to plants by 

 the portions of soot which are carried up the chimney Hues of the furnaces 

 for heating hot-water apparatus, steam boilers, and common smoke flues, and 

 diffused in the atmosphere, is considerable; and the unsightly appearance 

 produced is a worse evil than even the injury. As hothouse fires are seldom 

 required to burn bright there is no way of getting rid of the nuisance effec- 

 tually, except by burning coke or wood ; but in some cases where one large 

 furnace heats all the hothouses of an extensive range, as used to be the case 

 formerly at Messrs. Loddiges, Hackney, then some mode of burning the 

 smoke may be adopted. We have in p. 314. noticed Mr. Juckes's plan, which 

 we have since seen at work in the establishment of Messrs. Easton and Amos, 

 and consider by far the most effectual smoke-consuming apparatus hitherto 

 invented ; and we have now to describe that adopted in the printing-office of 

 the Messrs. Chambers of Edinburgh, the proprietors and publishers of that 

 admirable work, Chambers's Edinbicrgh Journal. Messrs. Chambers employ a 

 four-horse high-pressure engine. At first they adopted Ivison's patent pro- 

 cess for burning the smoke, which answered well, but they altered to a plan 

 which answered better, and which is thus described. 



" The furnace, which is of the usual construction, we keep closed with an 

 iron door. All the air required for combustion is admitted from the ash-pit 

 beneath. We, however, keep the mouth of the ash-pit closed also, and admit 

 air into it by a tube near the bottom on one side. Into the ash-pit is like- 

 wise conducted the pipe of waste steam from the engine, by which a constant 

 stream of steam mingles with the air, and ascends into the fire above. This 

 administration of steam with atmospheric air to the flame of the furnace de- 

 stroys the smoke. In point of fact, no smoke is observable from the chimney ; 

 certainly not more at least than from a small room fire, except when the 

 process is deranged by opening the furnace door to shovel in coal. The coal 

 being supplied and the door shut, the smoke instantly dies away, and speedily 

 disappears. The air-tube into the ash-pit is not conducted immediately from 

 the outer atmosphere, but from a series of tributary tubes from the respective 

 floors of our printing-office, by which means the foul air of the house is 

 drawn away and consumed. Of course the tube from the outer air will have 

 the same effect. To any steam-engine furnace this plan can be applied at a 

 most insignificant cost, and without any structural alteration," (W. Chambers, 

 in the Scotsman, May 13. 1843.) In our Volume for 1837, p. 370., a mode of 

 adding strength to the fire of a washing-house boiler by admitting the waste 

 steam from the boiler into the ash-pit, immediately under the bars of the grate, 

 is described ; and from the above information by Mr. Chambers it would ap- 

 pear that smoke is consumed, as well as strength added to the fire. 



Having sent the foregoing paragraph to an eminent engineer, he returned it 

 with the following remarks : — 



" Hothouses, conservatories, &c., have generally low chimneys, hence com- 

 bustion is very imperfect ; a jet of steam introduced beneath the bars quickens 

 the draught, and prevents the bars from becoming choked by clinker. In 

 factories where condensing engines are used, working with high chimneys, this 

 plan would not be economical, and the steam thrown beneath the bars might be 

 said to be nearly all waste ; the chimney causes sufficient draught and com- 

 bustion. In factories where non-condensing engines are used a jet of steam 

 from the exhaust pipe will do good by working the damper lower and accele- 

 rating the draught by the steam beneath the bars, as the steam would 

 otherwise be thrown useless into the atmosphere, while cold air must be 

 introduced to support combustion ; and I doubt not but that a certain portion 

 of steam would be found more beneficial, believing it to be composed of ele- 



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