As to the mere ventilation of the sewer itself, it could easily be effected by single drain pipes 6 inches in diameter, placed at intervals, from the sewer to the ash-pit of any neighbouring furnace. It would be probably to the advantage of the furnace itself, as even the tall stalks must sometimes make black smoke. A legislative enactment should require their owners to let them perform this service. It might require strong furnaces and plenty of them to effect it. A suggestion for getting rid of that “monster nuisance, London smoke” was made known in the Builder about 1859, by Messrs. Bruce Neil. It is thus described: “The plan consists in placing small tanks containing water over the chimney (the chimney-pots being fixed inside the tanks, and made of a spiral and bent form). The chill of the water gradually condenses the smoke, which becomes decomposed and destroyed, being precipitated at the bottom of the tank in the form of mineral tar. The water is turned on and off daily. It will be here observed that in the event of a fire in the chimney the flames cannot spread, as they are immediately quenched by the water in the tank. According to Mr. Bruce Neil’s calculation, the smoke of 80 tons of coal, if collected, will yield upwards of 28 barrels of tar, of 2½ cwt. each. He proposes that the Legislature, or the Society of Arts, should offer a premium to the person who will undertake to rid us of this monster nuisance and convert the smoke into tar, so as to make it applicable to commercial purposes. In the adoption of the above plan a slight alteration in the mode of ventilating our apartments is all that is required, he tells us.
As to the possibility of converting smoke into tar by such means as are above described, some doubts might be expressed if it could really be done; the remedy would be worse even than the disease, every household using yearly 20 tons of coal would have in that time to remove 7 barrels or 17½ cwt. of tar from their roof. The Builder, in publishing this suggestion, did not give any diagram or sketch showing how the process was to be effected. Mr. Bruce Neil no doubt made one, as he speaks of the alteration required in the ventilation of our apartments; a drawing would at least have explained how the water was to collect the soot, and how it was to have access to the flue in case of its being on fire.
The suggestion of collecting soot at the chimney-top by means of water was a valuable one, and there is no doubt it could be done to some extent, but not by encircling the pots with cold water, which would chill the smoke and prevent the soot from rising. A
Fig. 23.—Water chimney-vase for collecting soot.
| Half elevation. | Half section. |
design is here given, fig. 23, to show how it could be effected.
It will be seen that the chimney-pot or funnel has a zinc cover carried by stout ironwork surrounding it; a is the water, b the pipe to convey it away; it would be self-acting, and being washed by every shower would not be likely to get out of order. The rain-water must be looked for as to supply—to pay for high service for the roof of our houses to the water companies would not do.
Our climate is more damp than cold, and a considerable quantity of rain falls on our roofs. The zinc cover is spread out, so as to retain as large a portion as possible of the rain-fall. In winter, when there is most smoke, there is most water, with little or no evaporation. A pool of water could be thus collected, and the smoke projected over it would lose some portion of its soot, which could be floated away by the pipe into a receptacle provided for it in the back yard. The water might be sent into the drain and the soot left; or it could be sent into the drain as well.
The arrows in the diagram show the direction of the smoke, and the cover is so spread out and curved as to render it unlikely for any violent wind to flow out both water and soot into the street beneath.