The Fireplace. — Flue Construction and Smoke Prevention
An especial love for home comfort has always been an English characteristic. It has formed a species of national taste and pride even among our working classes. The constant changes of our climate are injurious to every class; the chief point of attraction in the English dwellings, during winter’s wet, cold, and fog, is centred in the fireplace. This has long been deemed the favoured spot where
“Social mirth
Exults and glows before the blazing hearth.”
The fireplace suits our climate; it is cheerful and attractive, but it gives its heat only by radiation. We are warmed on one side and chilled on the other, but neither the warmth nor the chill is too great to bear, and the occupant of the room can move into any temperature that suits him. In more northern climates the use of the fireplace would not be tolerated; there the cold is so excessive that an equal warmth must be diffused throughout the apartments, and flues in hollow walls, and closed stoves either in iron or brick are in the ascendant, as already mentioned in an earlier part of this work. But such means, by which the air is heated, and not merely warmed—and there is a great difference between warmed air and heated—would not be tolerated here. A puff of air from a closed stove caused by a back draught is not pleasant, and is very different from the honest puff of smoke from an English fireplace, that gives as a natural product of combustion, carbonic acid gas. But not one of these stoves, nor those that are called “smoke-consuming stoves,” make a good companionable fire—and this is not liked.
The common open fireplace has held its own, and will continue to hold its own, against the best-contrived stove that can be introduced in lieu of it. But it still remains to find such a construction as will remedy its serious defects. These are chiefly such as pertain to the flue; it is not to the stove that these belong, for that, thanks to our excellent makers, is quite perfect.
In our sluggish winter atmosphere the smoke leaves the open flue with tolerable certainty unless the flue is foul with soot; but when high winds prevail and the atmosphere is anything but sluggish, it teaches us the faults of the open flue, and volumes of smoke descend into our apartments. There are few occurrences in domestic life more vexatious and annoying than this; the numerous unsightly appendages in the form of cowls, turncaps, and windguards which appear alike on our houses, churches, and palaces, whilst they exhibit the ingenuity of our builders and workmen in remedying the trouble of smoky chimneys, demonstrate also the frequency of the misfortune.
When flues are carefully constructed, with the best modern improvements, and a due supply of air is admitted into the stove, a smoky chimney is an exception; still the flue forms only a simple open funnel for the passage of the smoke, and failures will inevitably often happen. A construction on a good principle should render these defects as trifling as possible. In our best houses—those constructed within the last twenty or thirty years—two kinds of the common brick flue are mostly in use. One is of the old-fashioned kind, having a section of 14 by 9 in., which was made originally of that size for the accommodation of the poor sweeping-boys. This is now retained only for the kitchen fire, which makes a large quantity of smoke, and for the rest of the fireplaces the flue known as “Cubitt’s” flue is employed, which has a diameter each way of 9 in. The author prefers the small flue, and always uses it in the buildings he has constructed. There are many persons who still maintain that the old-fashioned flue is the correct one, and it is still very generally used. There is an old saying about the proof of the pudding. In Belgrave Square, all the houses first designed and erected have the old-fashioned flue, and there are scarcely a dozen of the old chimney-pots left; all have been changed for tall-boys and other similar contrivances; one house has about 24 in one stack. No. 49, built by Cubitt about 35 years ago, and having the descending or sweeping flue, has the stacks exactly as at first constructed, with the exception only of a little doctoring to the kitchen flue. In the house opposite, No. 48, one of the first, the external stack alone, next the street, has no less than 17 tall-boys, two of which appear to be broken off. On the opposite side of the Square, in Chesham Place, is No. 38, built by Cubitt about 30 years; it has all the original stacks untouched.
The Cubitt flue can be recognised by the small peculiar cap on the chimney-pot, and several of these stacks remain in their original state. In Eaton Place and Eccleston Square, where this flue is used, the roofs tell the same story. In the first buildings erected by the author he used the large flue, and he now finds several specimens of chimney-doctoring on the roofs. In some large houses he lately erected at Queen’s Gate, in which the sweeping flue is used, there are several houses together without any disfigurement at all on the roof. He considers that the appearance of a tall-boy on one of them would be rather a proof that there was something wrong about the servants’ management of the fires, than an error in the construction of his flues.
A representation of this flue, and the manner of introducing it into a building, is here given. Fig. 1
represents a portion of the chimney-flue construction of a first-rate house; the lower chimney opening is in the basement, and above it are two others, one on the ground floor, and one on the first floor. It will be seen that there are three flues descending or taken down to the basement. The third flue belongs to the room on the second floor. The wall is two bricks thick, the flue 9 in. in diameter, and contained within the wall with no chimney-breast projecting. Fig. 2 is a plan of the flues on the ground floor, and fig. 3 of those on the first floor. Fig. 4 is a section of the fireplace opening; this is 3 ft. in height from the floor-line, the brickwork at top is splayed, and supported by an iron bar; these openings are always filled up with 4½ straight joint work, to be taken out when the mantelpiece is fixed. Fig. 5 is the chimney-pot and its cap, the latter opening at top 7 in. by 9 in. only; fig. 6 shows one of the sweeping doors, in which there are two to each descending flue. The latter three figures are twice the scale of the former. A plan and section of the chimney complete, with its marble mantel and stove, is given in figs. 7 and 8. The flue passes completely down at the back of the stove, the front is closed by an iron plate to a height of 2 ft. On this is fixed the moveable door or register, shut fully or partly over the flue when the stove is in use, and closed over the stove when the flue has to be swept. The arrows show the mode of admission of air to the front of the fire; it is brought through the floor and two openings in the back hearth from the outside of the house. This is generally kept concealed, and in order to ensure a supply of air to the stove the room should be kept completely closed.
To cause as full and perfect a combustion of the fuel as possible, a draught or current of the external air should be always admitted to the stove, and it could easily be placed under open management, so as to admit either a large or small supply of air, as required. Numerous patent processes to effect this are in use, but the most effective way of doing it is that shown in figs. 7 and 8: it is too simple for a patent.
Fig. 9 shows a method of admitting air above the architrave of the entrance door of the room. The opening is made about 2 ft. in length; this, after a little time, becomes marked by the blacklets coming in from the passage. The sweeping flue when the fire is lighted becomes very hot; the smoke ascends speedily and soon leaves it. The flue requires the stove to be formed expressly for it. Mr. Cubitt made the stoves only for his own houses, and the author had some difficulty at Queen’s Gate, in procuring stoves of the right pattern, for manufacturers prefer their own shop patterns, and some of these would have covered up half the descending flue. Those he used were supplied by Messrs. Feetham of Clifford Street, who are well acquainted with the use of the flue and stove. The flue is considered an excellent one; it is a builder’s flue, constructed solely of brick, and is certainly the best of the brick flues. The same attention was paid to it as was given to every part of Mr. Cubitt’s buildings. It may be asked, “Are there no other kinds of flues constructed of superior materials?” Yes, certainly there are; particular attention has often been paid to the flue. There is Hiort’s circular flue, formed in each course of four wedge-formed bricks. Mr. Hiort held a very important position; he was Treasurer of the office of Works at Whitehall, and his flue was extensively used in some of the Government buildings and the houses in Carlton Gardens. It did not bond well with the brickwork, so we have Mr. Moon’s improvement upon it. This was considered not sufficient, and another patent was taken out in 1844 by Messrs. Clark and Reed for its further improvement. The flue was an excellent one, but on Mr. Hiort’s retirement from the Government Board, it went out of use.
There is Seth Smith’s metallic chimney lining, which makes an excellent flue; the lining is a pipe of from 5 to 10 in. in diameter, built in the brickwork. About 150 of these flues are at the Pantechnicon. Mr. Smith announced his determination of never building any house above the value of 30l. per annum, without using them. They could be introduced, to form perfect linings to chimneys in buildings already erected, and allow the stack to be reduced in height, without having the unsightly appearance of contractions made above them. The drawback to the use of these tubes by builders was the price. Without any royalty, the 9 in. tube cost 3s. 4d. per ft. run, the curved tubes 4s. 3d., the starting tube 3s. 8d. The tubes were of the exact form of drain pipes, and they were cheaper, and as effectual.
If Mr. Smith’s metal tubes had been introduced into a large brick flue, they would have rendered the latter an efficient shaft for ventilating every room in its upward course, openings being made for the purpose at the upper part of the rooms. This mode of ventilation was applied to hospitals on a large scale by the late Mr. Jacob Perkins several years ago, with perfect success.
Denley’s flue, introduced in 1843, is believed to have been the precursor of that used by the late Mr. Thos. Cubitt at Belgravia and Pimlico, and there is a great resemblance between the two; but Mr. Denley’s flue has nothing like the simplicity nor ease of construction of Mr. Cubitt’s. The downward flues were merged into one at the basement, and all the soot and cinders were collected or thrown down into a fire-proof box, which must have stood out in the lower rooms, from which they had to be removed. The flues were swept from the roof, the register doors of the stoves being closed, and there was no provision for sweeping the flues between the basement and the stoves. Joined to his system for sweeping, was one of air flues which brought a current of air direct from the exterior of the house to each fireplace.
We have several flue systems which have ventilating flues in connexion with them. Boyd’s flue forms the wythes, or half-brick spaces between the flues, of iron plates, and the open spaces thus gained make ventilating passages. Mr. Doulton’s combined smoke and air flues are manufactured in terra-cotta, in three sizes; the air flues follow the line of the smoke flue, the passages being quite distinct, as in Mr. Boyd’s. The heat from the smoke flue causes a current in the air-flue which carries off the vitiated air admitted by openings near the ceiling. The common drain pipes and the glazed fire-clay pipes make good flues; the use of these pipe-flues has greatly increased during the last few years; they improve the draught, and clean easily. Flues for ventilation from rooms should, like Arnott’s ventilator, enter into the smoke or a hot ventilating flue. Arnott’s ventilator requires careful adjustment, to be balanced in such a way that it should stand closed on a calm day.
The superior patented flues, as they are of considerable cost, and take extra time in construction, are only used in the better class of buildings, or in those erected under the express direction of the owner. In speculative buildings they are never used. The time required for their construction beyond that of the common brick flue, being regarded by the builder as so much money lost.
The great desideratum in a flue is to make it pass off its smoke quickly, and this the small size flue effects more certainly than the larger one, as it warms sooner and keeps its heat longer.
An enthusiastic admirer of the descending or sweeping flue once told the author that with a good fire in the grate, if a kettle of water could be placed on the top of the chimney-cap the water would soon boil, even if the flue were fifty feet high. The flues constructed of metallic or earthenware casings retain also the heat longer, and keep hotter. It may be imagined that with these flues, and the large quantity of gas lamps in the streets, why the temperature of London should be always some degrees higher than that of the country. In winter snow may be seen in the suburban fields, but none is found in town.
Architects have often been blamed for not inventing a good system of flue-construction, not only for the prevention of smoke in our dwellings, but for the hindrance of its presence in the atmosphere. Several, and most excellent attempts, have been made for the former, but very few for the latter, which is one of far greater difficulty. Yet this is one that admits of a cure, great as the evil is. The chimney flue might be so improved as to effect a more certain and larger ventilation of our houses, without any addition of ventilation flues. The introduction of the French Mansard roof with us, one from a country where coal fires are not in use, renders it almost imperative for the chimneys belonging to such buildings to have a different construction, for chimneys when placed against a building or roof that overtops them, are sure, as they are at present made, to become smoky: the wind returning owing to the high construction, and descending in the flues. The following few designs are offered to cure these various evils.
Accepting as a fact that tall-boys, and the other iron and zinc constructions, are useful appendages, there can be no reason why they should be so used as to disfigure our buildings. Some of the finest specimens of architecture in the Metropolis serve only as pedestals to an ugly collection of cowls.
The author proposes to form the upper part of the flues in a building, for a length of about 15 to 20 feet, entirely of iron or other tubing, in square, round, or oblong sections, of a less diameter than the brick flues to which they are attached. This tubing is gathered up in groups, and carried out at an angle of 45° towards a centre stack: the tubes in direct contact with each other, having no brick wyths, except one or two to strengthen the stack.
It is obvious that if only one of the flues be in use, it would moderately warm those next to it; and if the whole of the flues of a building were constructed on this plan, and two or three were in use, such a power would be obtained as would effectually ventilate every room; the action would be continuous and imperceptible, and a fire could be lighted in any one without the risk of return smoke from a cold or damp flue.
Thus the heat now wasted in the atmosphere by the action of the common flue, would be partly retained and turned to use, and the draught of the flue very much improved.
This tubing could be readily introduced into either old or new buildings, as the introduction does not involve taking down more than twelve feet of the brickwork, measuring from the top of the coping. The tubes could never become sufficiently heated to be dangerous, and less brickwork would be required.
They might be made either of zinc or earthenware; cast-iron would be objectionable on account of its weight. It will be seen that they admit a better mode of sweeping than that now practised, and they could easily have some kind of capping to prevent down-draughts.
These “stack flues” should commence from the attic or upper storey of a building, at about six feet from the floor; sweeping doors should be placed beneath them, so as to give the sweep command of the flue beneath as well as above.
Each flue should be composed of three separate forms of tubing, by which the various directions and turns necessary for the construction might be obtained.
Fig. 10 gives the representation of the three forms; 1, is the first; this is placed directly over the brick flue, and gathers it up to a size having an internal dimension of 6 + 4½. It is 21 inches in height. 2, the second piece, is on a curve; the top and bottom lines, if carried on, would form an angle of 45°; it is about 18 inches in height, and internal size 6 + 4½. The third, 3, is a straight piece, internal size 6 + 4½, the lengths various. Fig. 11 gives a plan of four flues and an elevation of the commencement of two. The sweeping doors are shown below. The flue without a door is the ventilating flue for the basement. The ease with which this tubing can be grouped is shown in fig. 12. The stack consists of five flues; the tube, 2, connects them together below, and separates them above. The stack above the roof is 4 feet 9 inches in length.
Fig. 13 shows, in the upper plan, how the flue wall could be reduced in thickness, made a brick and a half only, with a two-brick block at each end; it contains coupled and tripled sets of tubes.
The middle plan shows nine flues grouped together, the centre being that belonging to the kitchen. The last plan shows a group of six in a two-and-a-half-brick wall; by the side of this are two flues of the common construction, 14 inches by 9, made of this size to enable a boy to get up to the top and place his head out of the chimney-pot.
The tube 1, fig. 12, can have its position reversed, as shown in fig. 14; six flues can thus be grouped together, as shown in the third plan, fig. 13. The elevation of this stack is given in fig. 15.
For a covering to these tubes figs. 16 to 20 show ornamental pots and their sections. The only merit in these may be that they are of a more ornamental character than any that have ever been introduced; they are formed of zinc, supported by a stout dwarf iron railing. The intention is to permit the smoke to escape in any direction, either upwards, sideways, or downwards, sheltering it as far as possible from any action of the wind, and rendering of little consequence whether the stack is high, low, unsheltered or otherwise. If any sudden gust of wind take place and the smoke be driven back, the capping provides larger outlets for its escape than the small aperture of the flue itself; in other words, it is easier for the smoke to pass in any direction rather than return down the flue.
The stack flues are only, in fact, tall-boys boxed up and not put out in the cold, and it is presumed they would be sufficiently powerful, from their warmth, to ensure a good passing off of the smoke, and secure ventilation to the building.
A forced ventilation to our dwellings, in ever so slight a degree, is a matter of importance. By the proper construction of these proposed stack flues it is presumed that any amount of ventilating power, self-acting and continuous, could be obtained. Their introduction alone would be beneficial; combined with the flue pedestal, to be described, the tubes could be led into one general upward shaft; by either plan we should have some command over the smoke, while the roofs of our buildings might be made ornamental and picturesque. It would be a treatment of bituminous coal alike artistic and novel, surprising to foreigners and creditable to ourselves.
It remains to show how the open character of the flue could be taken away (this forms its chief evil), and how a chimney-stack may be formed without chimney-pots. The late Lord Palmerston, when Home Secretary, proposed the abolition of chimney-stacks, and the use of only one chimney-stalk for each separate dwelling. In 1856, a commission was appointed to inquire into the best modes of warming and ventilating the apartments of dwelling-houses and barracks. Their report, given to the General Board of Health, was published in 1857, and it afforded a section illustrating “the principle on which it was proposed to construct dwelling-houses.” There was only to be one flue, and this of metal 10 inches in diameter, enclosed in a large brick flue, which was to serve for ventilation. In the metal flue were to be inserted the flues of the several fireplaces; these were placed back to back, and if the register doors of the stoves were open, a person in one room might both see and converse with another in the next; the music of a pianoforte in one room could be heard in them all; this construction was taken up through four storeys, there being eight fireplaces. For one fireplace alone it would have been perfect, but the smoke from the two kitchen fires would have been sufficient to have choked the flue and caused the smoke to enter into the whole of the eight rooms.
The chimney-stack might possibly be lowered, and it certainly could be constructed without chimney-pots, but each separate flue must have its own outlet. A design for this, one that should take away the open character of the flue, and fit the stack, possibly for the Mansard roof, is here given.
In fig. 21, a a are the flues, delivering their smoke into a large ventilating flue, b. The warm smoke would induce a current of air to enter at c: any current will have a tendency to draw another with it, so that the smoke leaving the flues c c would be taken out at d by the current of air at c.
This is the principle upon which all the best ventilating chimney-pots, tall-boys, and cowls are made, and it is a very sure one. The jet of steam in the funnel of the locomotive, drawing the smoke from the fire, and creating a draught, is adopted on the same principle.
In scientific language, the established law both of pneumatics and hydraulics is that when two currents of fluid matter passing in the same direction, but in separate channels, arrive at any point of confluence, the stronger current draws the other along in its course, and with a considerable portion of its own velocity. Thus the force of the wind, which checks in other instances the action of a chimney-draught, is made to produce a stronger draught, exactly in proportion to the violence with which it blows.
Returning to fig. 21, a current of air, instead of coming in at the opening c, might come in at d. It would then have a tendency to blow down the flues a a: to prevent this, the opening d could be closed, and an upright stalk placed at e,—this should have a downward shaft, a place for soot, and a sweeping door.
There is still another mode of treatment; fig. 22 represents the flues grouped, each with a separate ventilating flue, the smoke delivered being at the side of each.
The stack might be covered with zinc in the ornamental style with which that metal is now treated.
It is probable that if a stack on this principle was placed parallel to the side of one of these Mansard roofs, it would be secure from the ill-effects of any wind returning against it. The author will not vouch for its success, but it is offered here to the attention of architects and builders as an experiment worthy of trial.
It has been affirmed that the smoke of towns, however disagreeable it may be to the inhabitants, neutralizes the poisonous effect of the gases caused by sewers, &c. If it was possible wholly to remove carbon evolved by smoke, our towns would almost be uninhabitable, and they represent that any scheme for getting rid of smoke must be combined with one for getting rid of the exhalations from sewers at the same time. If the two evils were brought together, they would neutralize each other, and both could then be got rid of at one operation. The best scheme for this is a matter of important consideration, but few have been proposed.
It may be asked, what has a work on Picturesque Architecture to do with either smoke or sewer gases? The author in reply considers that buildings never will look picturesque while they are covered with great patches of soot. An eminent sculptor once affirmed that the statues of London were improved by their soot covering, because it made them stand boldly out against the sky. But those beautiful decorated smoke towers which stand on the roof of the Houses of Parliament, and which are as black as Erebus, look anything but pleasing, standing amidst the whiter front of the rest of the building. Besides, tall-boys are beginning to make their appearance on the roof under the Victoria tower, and these certainly form no part of the architecture, but appear monstrously ugly; consequently smoke and its abolition are clearly questions to be considered in relation to Picturesque Architecture.
A plan for removing smoke from the atmosphere of towns, and at the same time ventilating buildings and sewers, was proposed in 1849 by Mr. Flockton, surveyor to the town trustees of Sheffield,F a town as much begrimed with sooty smoke, only in a smaller way, as the Metropolis.
The proposal was, that under the footways along the side of every street and lane, flues should be constructed of sufficient capacity to carry off all the smoke and other atmospheric impurities, these flues all converging, upon a general plan, to tall shafts or chimneys at some distance from the town, and supplied with furnaces. These, when the fires were once ignited, would give a fire produced by the combustion of the inflammable gases accompanying the smoke, and which would burn spontaneously in a similar manner to the combustion of foul air from old shafts connected with coal mines. The combustion might be assisted by jets of coal gas, in a fire of coke.
In very large towns it would be necessary, Mr. Flockton added, to divide the whole into districts, and to erect towers in the centre of each, to which all the flues should converge. He published a plate, showing two large dwelling-houses, with a street between, the common sewer in the middle of the carriage way, and the smoke flues on each side under the footpaths, also showing the connexion between the sewer and flue. The alteration proposed to houses already erected consisted in converting ascending into descending flues; turning the smoke from the chimney-top into the latter, and from thence into the street flue. This operation would have necessitated the pulling down and rebuilding of the flue walls. The street smoke flues, in order to carry off the smoke from a few thousand chimneys, would require to have been made of a size even larger than the sewer itself. Provision must have been made for clearing out the soot, for the smoke would have been cooled and the soot would accumulate in large quantities in them.
The same scheme, with similar constructions, was proposed by a foreign gentleman, who took out a patent for it in 1850 (No. 13,061). His plan was a very grand one; he did not propose alterations in existing buildings, but pulled them down and gave designs for a new city.
A more practical plan was proposed about 1851 by Mr. Devey, a surveyor of Furnival’s Inn. A model of his invention was in the Great Exhibition of 1851, and it is described and an engraving given of it in the illustrated volumes published by the Royal Exhibition Commissioners at the close of the Exhibition. The model is now in the Museum at South Kensington. Mr. Devey’s plan was to make only one descending flue to each building, to which the flues at the top could be either connected or not, at pleasure; the descending flue was carried to the sewer in the middle of the street, and the action of this was to be assisted by the heat of the kitchen fire. He says, “The smoke would be drawn down by the current produced by exhaustion in the sewer, the action being assisted by the kitchen fire.” Mr. Devey did not propose to have furnace shafts, but depended entirely upon the sewer acting as an exhaust.
In this scheme the objections were, that one descending flue was not sufficient to carry off the smoke from several chimneys, and the sewer certainly would not act as an exhaust without its being connected with upright furnaces. Our sewers generally have ventilating openings which permit their odours to ascend into our streets. Soot would no doubt neutralize these odours—this, a paper in a late Quarterly Review (April, 1866) admits. First, speaking of the sewer gases, the reviewer says: “These offensive gases have often engendered formidable diseases, and have, in several instances of late, been clearly shown to have caused the outbreak both of typhoid fever and cholera.” Of this the author has had proof during the outbreak of cholera in London in 1849. He was superintending the construction of a mass of buildings in one of the worst dwelling districts in London. This builder, who had just finished the erection of Harrington House, a description of which is given in this volume, died the first night of the outbreak in the greatest agony; he was a strong robust man; from one to three deaths took place in every house in the locality; a black flag was put up in the streets, and the foul fiend reigned for a while supreme. A large mass of the worst buildings have been cleared away, and model lodging-houses erected, but a considerable portion of the rotten old structures remain, the sewers are untouched, and the visitation of the cholera forgotten.
The Quarterly Review says there is no reason why ordinary sewers should not be made to serve the double purpose of carrying off smoke and sewage at the same time, provided they were connected here and there with high shafts rendered powerfully expansive by furnaces; and adds, “sewage would be improved for agricultural purposes by admixture with soot, which is an excellent manure, and the noxious qualities of the sewer gases would be destroyed.” Whether soot would increase the value of sewage or decrease it, is a question for chemists to decide; a generally increasing opinion is, that our method of using sewage by liquefaction and sending it away, is a mistake, and renders it quite worthless, and that the system of dry earth-closets is more conformable to Nature’s laws.
The subject was taken up in 1857 by Mr. Peter Spence, of Manchester, a large alum manufacturer.G This gentleman states that the “blacks,” the horror of the Londoner, are guiltless of any deleterious effect to human health, as carbon is one of the most anti-putrescent of bodies, and while floating in the atmosphere over everything, arrest and destroy noxious and miasmatic vapours. Perfect freedom from smoke would, if accomplished, only increase the evil arising from the purely gaseous results of combustion. He proposed a system of atmospheric or gaseous sewage, and the complete removal of all their gases to a safe distance from our towns. He would combine this gaseous sewage in such a form with town drainage as would bring all the liquid sewage into contact with the gases from our furnaces and house fires, the liquid sewage being kept from all surface drainage. The same liquid and fœtid mass of sewage he would concentrate in an innoxious form, to be converted, in a convenient place, where it might with perfect safety be manufactured into manure more valuable than the richest guano.
For effecting this all the gases from our coal combustion would have to be conveyed along the same tunnel with the sewage to centralizing conduits converging to a point, where an immense chimney, 600 ft. high, should be erected, to discharge these gases into the atmosphere, the ascensive power being obtained either from the retained heat of the gases, which would probably be found quite sufficient, or if not, artificial heat could then be applied to effect the object. The chimney should be of the internal diameter of 100 ft. at the top, and 140 ft. external diameter at the bottom. This would take the smoke from 500 chimneys and every particle of foul emanation from the sewer, and every leak or opening to the upward air from these sewers would not then emit foul gases, but draw in fresh air with a pressure or suction of three and a half pounds per foot, and with a velocity of 40 feet per second. This gentleman says: “It is idle to talk of trapping, and thus confining gases evolved under ground; exit they must and will have, and when you imagine you have secured them in one place, you will find them pouring out in another.” He makes this plain by an illustration. He took an old-fashioned detached house; after entering into possession he found frequently very disagreeable smells, especially after rain, a change of wind, or a fall of the barometer; it may be remarked here that it was not necessary to take an old-fashioned house to find out this; in more modern built houses in London, after a fall in the barometer or rain, such a thing is repeatedly occurring. Mr. Spence, to cure the evil in his old mansion, exhausted all the remedies which the philosophy of London schemes acknowledges; he trapped all the exits from the sewer with the most approved patent girds; all slopstone pipes were cut and water-luted. But this was of no use, the smell came through the very walls and floors, and one bedroom on the first floor, which showed no connexion with the sewer, was quite uninhabitable. He adopted a plan which succeeded: a branch from the main sewer was brought right under the kitchen grate, from that a pipe of cast iron, four inches in diameter, was carried up through the brickwork, and the open top projected into the chimney a yard and a half behind the kitchen fire, above the fire. When this fire was again lighted, in a few hours the house was perfectly sweet, and the distant bedroom, uninhabitable before, has been slept in ever since. When this nuisance occurs in a London house the only remedy is to open the doors and windows to get rid of it, as we are not allowed to meddle with the sewers. Disagreeable effluvia in dwellings often occur, and baffle every endeavour to trace from where they proceed; in every case it is from choked-up drains or the sewer, and the decomposition of animal and vegetable matter therein retained.
As for Mr. Spence’s scheme, its grandeur almost stops its execution. It is well known that in all large manufactories, and in gas works, a tall chimney serves to draw out the smoke from the numerous fires, and it forms a smoke-outlet for them all. In most of these places the fuel is used up so completely that it is only the gases of combustion that are drawn away. Mr. Spence’s scheme has been successfully tried in its application to private residences, and also on a large scale to the new Assize Courts in Manchester. It was adopted by one of the architects in the competitive designs for the New Law Courts in London.
If these tall shafts and furnaces were applied in London, it may be questioned whether the smoke in cooling would not deposit the soot in the sewer, and this must be removed, if not run off by water. The flues connecting the house fires with the sewer would be partly horizontal, and these would certainly fill with soot, and no machines we have at present in use could clean out these flues from above. The operation must be performed from within the sewer, and then these flues being unsupplied with drain-eyes at their entrance to the sewer, would form so many open channels for the passage of the sewer gases into the houses. This would be the case in a very great degree where there were no fires in the stoves and their register doors were open. It would require an immense consumption of fuel in the high stalks to cause a current to prevent it, and the furnaces must be close together to lessen the cooling effects of cold currents of air from flues not in use.
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 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.
Certainly coal smoke is a great nuisance; it is yearly pointed out as such by our paper the Times, in one, probably two, very excellently written leaders. Even the youngest member of the press, the Echo, in one of the common London fogs occurring in April, 1868, thus remarks: “The most sad and remarkable circumstance about the fog of yesterday was that the newspapers and people in the streets spoke of it as a ‘visitation,’ as a ‘gigantic pall,’ as if, indeed, the black darkness was something as strange and unaccountable as a fall of frogs or fishes from the sky. Of course it was nothing but our own familiar coal smoke which stopped the way of the sunlight. It is most lamentable that Londoners are becoming so used to this filthy nuisance that nothing more than a passing exclamation is uttered when it is forced down upon them in such volumes as to produce almost the darkness of midnight at midday. If ‘cleanliness is next to godliness,’ then the people of London must have been yesterday the most ungodly people in the world, for nothing would remain clean which was exposed to the fog of that morning. A plague of locusts would not create more terror and sense of ruin in any foreign capital, where every article of dress and furniture and house decoration, both external and internal, would have been regarded as spoiled by the loss of freshness. But London received its coat of dirt yesterday, and to-day only wonders with the remark ‘how dark it was!’ Will nothing move us to abate the nuisance? Is there no hope but that distant one of the exhaustion of our coal-beds? Must we inhale coal-blacks, and always contemplate dirty houses and grimy furniture? Is it not possible by smoke sewers, or some contrivance or machinery, to relieve us of this plague?” It is very possible it could be done with the greatest ease, but at some first expense; and in some generation or other it will be written that it found London foul and left it sweet, and there will be a time when this will be appreciated; and the man who gives the city the pure atmosphere of a small country town will receive all due honour and acknowledgment, that is, when he is in his grave and securely buried.
The public have so long been accustomed to be choked with smoke, and their health affected by deleterious gases, that they look upon the proposal of any scheme to secure pure air as the hallucinations of dreamy philosophers or inexperienced Utopians.
None of our present flues can, in the very slightest degree, stop these aqueous vapours from ascending into the atmosphere, neither can they effect any purification of the smoke, or retain the blacks for any useful purpose; and it is of no use disguising the fact that any contrivance or appliance, to effect either of these most desirable objects, must consist of an additional construction to the flue, which will be attended with additional expense, and require extra attention. Therefore any such appliance, if introduced, should be effectual, and repay such additional cost to its owner, by a saving, or at least a more economical use of fuel.
The appliance to the flue the author has to recommend, he considers will not only cause an economical use of the fuel by not permitting the present waste of heat, but it will purify the smoke, and retain the blacks for any useful object to which they can be applied.
The principle of the best-constructed flue at present is to get rid of all vapour, smoke, and soot as soon as possible, without the slightest consideration for the people outside. That the smoke should not return to annoy the occupants within the house is the aim of the constructors, and to secure this, the waste of heat in the chimney, and the consequent waste of fuel, is considered of no importance, for is it not the hot smoke that carries up the soot and ventilates the apartment?
This operation of the flue could be taken advantage of. In the construction of chimney-flues in a wall they are often turned at an angle to the right or left to pass an obstruction, such as a fireplace or timber placed within or against the wall. A flue could easily be taken out of the wall and returned, and if the part so taken out was formed in cast iron with a small cistern of water at top, it would become a warm-water pedestal, and could moderately warm or air an apartment in which it was placed; the author calls this the flue pedestal, and it is represented in the following cut.
It is about three feet six in height, not much higher than a small cabinet. The door could open, and a small tap supplying warm water for domestic use would be seen. Thus the upper rooms of a house could be warmed or aired by the fires below in perfect safety, and the present waste of heat in the flues prevented. This would be economical, as in most cases no fires would be necessary in the upper rooms.
The flue thus brought out in iron could contain a fine spray of water, that would draw up the smoke, and take down its vapours and soot at the same time into the sewer.
Fig. 25 shows a section of the flue thus brought out. The wall is two bricks thick, the flue a, is 9 inches in diameter, d is the cast-iron flue, and another, e, shaped like a funnel, is placed behind it, to collect the soot and water, and pass it off through the pipe h. The cistern is partly within the walls and partly covering the two flues. It is not necessary that the water in the cistern should supply the spray: that might be done by a separate pipe with a tap to turn off and on as desirable; b is the moveable pedestal covering the whole.
The adaptation of this simple contrivance to any kind of domestic chimney-flue is not a very difficult operation. It is only necessary to take out the brickwork in front of a flue of a height of 4 to 5 feet, and then introduce the iron flue, gathering up the brickwork beneath it; the section, fig. 25, supposes the iron flues to be in an external wall; should it be required in a party wall the soot goes off at g g, to be conveyed outside the building in the nearest way; doors are provided for the purpose of sweeping; any down draught of air in the chimney might expend itself in the soot flue, and the smoke having passed the spray could not return. The spray of water should be equal to the whole width of the flue, and proportioned in strength to the work it has to do; the smoke from a whole group of flues might be conducted to one powerful spray, one upper flue or chimney would then suffice for the roof, while the soot and flues in any number might be formed into one before passing to the sewer.
The pipe h, shown in fig. 25, would not form an open communication with the sewer; it would be supplied with a flap-cover or drain-eye, like the common house drain at its extremity. This would open only when sufficient water and soot was behind it, and close when it was passed. It would not require sweeping, the water keeping it clear. It should have another kind of drain-eye to that at present in use, the lid, or flap of which is hinged from the top, the soot floating on the surface of the water, would require the flap to open from below. Fig. 26 shows the kind of drain-eye that would be required.
If it was not for the difficulty of the present form of drain-eye to our houses, the soot flue might discharge its contents into the house drains at once, below the trappings; there is probably no absolute necessity at all for drain-eyes at the termination of house drains, their use is to make precaution doubly sure, to prevent the rising of the gases from the sewer, and to keep out the rats, to prevent them, by getting through the traps, from entering the house.
Experiments were made with a shower of water in Mr. Cubitt’s descending flue. It will be seen by inspecting the figures 1 to 8 that these flues could easily be formed into one, and taken into the drain; the experiment did not succeed, as none will, that brings heavy smoke in opposition to a water-fall. The smoke must go with the current or water-shower, and not against it.
The flue pedestal, with its water-spray, is the whole of the contrivance by which the author believes the smoke of the domestic hearth could be got rid of, or rendered inoffensive. What the action of the water would be on the gases that escape from the fuel he cannot say, but he presumes it could not be other than beneficial.
He experimented on the subject a few years ago, and had a stove and flue erected about ten feet in height; the lower part of the stove was of brick, the upper part with the cistern of zinc. The coal fire was lighted, and as soon as black smoke appeared at the chimney-top, the water-valve was lifted and about 16 fine jets of water were sprayed against a piece of loose perforated zinc, suspended in the flue; this zinc is shown in fig. 25; in the second flue e (it should have been marked f, but by a mistake in the cutting it is made d), the smoke had to pass through under this perforated zinc to get to the chimney above. On the instant the water was applied, the smoke appeared at the chimney-top of a light colour, and it came out of the soot receptacle, placed a little height above the ground, nearly as much as it did at top, and of a similar light vapourish character,H a sure sign that it was drawn down by the current of water. Soot in large quantities was soon seen in the receptacle; the author has not ascertained the quantity of soot which would be obtained by this process from a ton of coals, but he believes it would be very considerable, possibly two sacks or more. As clean unmixed soot is worth in London 2s. 6d. per sack, if this soot were retained it would pay for the extra expense of the water, and the retaining of it, and to carry off the water would be an easy operation.
The “blacks” are good things at present in their wrong place; they could in the way proposed be very easily got rid of, and if it were possible to cut into all the chimneys of London and apply the remedy, the whole of the soot, which at present escapes into the atmosphere, might be caught and passed into the drains; it would there probably fully deodorize them. It is certainly not possible, from the herculean nature of the task, to disturb the whole of the chimneys of London, but the worst only might be operated upon, such as the chief kitchen flues of the great establishments, which are continually sending out black smoke.
Among the chief offenders are our bakers, nearly twenty of them being fined weekly for this by the magistrates, and for fires occurring in their chimneys. It appears that the Smoke Nuisance Act bears hardly upon them; the smoke-consuming apparatus forced upon them by the Act has utterly failed in its purpose, and it is impossible for them to comply with the requirements of the Act, and carry on their business in a satisfactory manner either to themselves or the public. They have applied to the Home Secretary for relief, and a bill to repeal so much of the Act 16 and 17 Vict. that relates to bakehouses has been in contemplation.
There would be no difficulty in placing a flue pedestal in their flues at any height above their oven fires; it would not only relieve their neighbours from the annoyance of black smoke from their chimneys, but it would secure the chimneys themselves from taking fire. The water need only be turned on when required, when black smoke was being made, and if they chose to collect the soot the expense of the operation would be trifling, if anything, beyond the first expense of the flue pedestal, in the end.
In large country houses the flue pedestal would warm the upper rooms or passages, and cause a more equal temperature in the building; this, together with the practicability of collecting the soot for agricultural purposes, might be an inducement to its introduction. Water could be lifted to the roof of a country mansion by that ingenious contrivance the hydraulic ram, and passed off to its original source when done with, the soot being left behind.
The beautiful self-acting machine, known as Gwynne and Co.’s improved hydraulic ram, is peculiarly adapted for raising or lifting water to any required elevation. It is necessary to have a fall of water to work it, and the greater the height of the fall, the more effective will be the machine. In favourable cases it will raise water thirty times higher than the fall working it. The greater the height of the lift, of course the less will be the quantity raised in a given time. This machine can be made to deliver comparatively large quantities of water, either in tanks on the roofs of houses, or in farmyards for filling ponds. It will work day and night without any attendance or expense after it is once fixed. Two or more rams may be used to force through the same pipe, or rising main. Where a continuous stream of water to work the machine cannot be obtained, a spring, or even rainfall, or drainage may be stored up in a reservoir or dam, and made to work the ram.
The expense of these machines is not excessive, as the following table will show:—
| Diameter of Feed Pipe. | Diameter of Delivery Pipe. | Approximate Number of Gallons of Water raised in a day of 24 hours. | Price of Ram, complete, with all the accessories, but exclusive of Pipes. |
| Inches. | Inches. | £ | |
| 2 | 1 | 800 to 1150 | 12 |
| 3 | 2 | 3000 to 4000 | 24 |
| 4 | 2 | 4000 to 5000 | 34 |
A small room or enclosure must be erected to contain the machine.
The question of how far the removal of smoke from the atmosphere would affect the various gases of combustion floating therein is a question for the chemist. The plan that has been here proposed is founded on the supposition that Nature’s law, relative to the diffusion of gases, permits only carbonic acid gas, the chief product of combustion, to remain in the proportion of 1 in 2000. The introduction of so much water in the sewer, where its presence already is considered an injury to the sewage, is an objection, but the present system of drainage requires a plentiful supply of water, to prevent stoppages or choking. Should the dry earth system ever be generally introduced, the present sewers would serve to remove liquid sewage and all products of combustion. The operation of the sewer in any way in receiving this smoke and soot, would permit the full and cheering light of the sun to shine alike in country and town.