Chapter XI: Part 11

In placing the plumb-line against the breast of the Chimney, in order to ascertain how far the new back is to be brought forward, great care must be taken to place it at the very top of the breast, where the canal of the Chimney BEGINS TO RISE PERPENDICULARLY; otherwise, when the plumb-line is placed too low, or against the slope of the breast, when the new back comes to be raised to its proper height, the throat of the Chimney will found to be too narrow.

Sometimes, and indeed very often the top of the breast of a Chimney lies very high, or far above the fire (see the figures 13 and 14, where d shows the top of the breast of the Chimney); when this is the case it must be brought lower, otherwise the Chimney will be very apt to smoke.--So much has been said in the First Chapter of this Essay of the advantages to be derived from bringing the throat of a Chimney near to the burning fuel, that I do not think it necessary to enlarge on them in this place,-- taking it for granted that the utility and necessity of that arrangement have already been made sufficiently evident;-- but a few directions for workmen, to show them how the breast (and consequently the throat) of a Chimney can most readily be lowered, may not be superfluous.

Where the too great height of the breast of a Chimney is owing to the great height of the mantle, (see fig. 13,) or, which is the same thing, of the opening of the Fire-place in front, which will commonly be found to be the case; the only remedy for the evil will be to bring down the mantle lower;--or rather, to make the opening of the Fire-place in front lower, by throwing across the top of this opening, from one jamb to the other, and immediately under the mantle, a very flat arch;--a wall of bricks and mortar, supported on straight bars of iron;--or a piece of stone (h, fig. 13).--When this is done, the slope of the old throat of the Chimney, or of the back side of the mantle, is to be filled up with plaster, so as to form one continued flat, vertical, or upright plane surface with the lower part of the wall of the canal of the Chimney, and a new breast is to be formed lower down, care being taken to round it off properly, and make it finish at the lower surface of the new wall built under the mantle;--which wall forms in fact a new mantle.

The annexed drawing fig. 13, which represents the section of a Chimney in which the breast has been lowered according to the method here described, will show these various alterations in a clear and satisfactory manner. In this figure, as well as in most of the others in this Essay, the old walls are distinguished from the new ones by the manner in which they are shaded;-- the old walls being shaded by diagonal lines, and the new ones by vertical lines. The additions, which are formed of plaster, are shaded by dots instead of lines.

Where the too great height of the breast of a Chimney is occasioned, not by the height of the mantle, but by the too great width of the breast, in that case, (which however will seldom be found to occur,) this defect may be remedied by covering the lower part of the breast with a thick coating of plaster, supported, if necessary, by nails or studs, driven into the wall which forms the breast, and properly rounded off at the lower part of the mantle.--See fig. 14.

CHAPTER. III.

Of the cause of the ascent of smoke. Illustration of the subject by familiar comparisons and experiments. Of chimnies which affect and cause each other to smoke. Of chimnies which smoke from want of air. Of the eddies of wind which sometimes blow down chimnies, and cause them to smoke. Explanation of the figures.

Though it was my wish to avoid all abstruse philosophical investigations in this Essay, yet I feel that it is necessary to say a few words upon a subject generally considered as difficult to be explained, which is too intimately connected with the matter under consideration to be passed over in silence.-- A knowledge of the cause of the ascent of Smoke being indispensably necessary to those who engage in the improvement of Fire-places, or who are desirous of forming just ideas relative to the operations of fire, and the management of heat, I shall devote a few pages to the investigation of that curious and interesting subject.--And as many of those who may derive advantage from these inquiries are not much accustomed to philosophical disquisitions, and would not readily comprehend either the language or the diagrams commonly used by scientific writers to explain the phaenomena in question, I shall take pains to express myself in the most familiar manner, and to use such comparisons for illustration as may easily be understood.

If small leaden bullets, or large goose shot, be mixed with peas, and the whole well shaken in a bushel, the shot will separate from the peas, and will take its place at the bottom of the bushel; forcing by its greater weight the peas which are lighter, to move upwards, contrary to their natural tendency, and take their places above.

If water and linseed oil, which is lighter than water, be mixed in a vessel by shaking them together, upon suffering this mixture to remain quite, the water will descend and occupy the bottom of the vessel, and the oil, being forced out of its place by the greater pressure downwards of the heavier liquid, will be obliged to rise and swim on the surface of the water.

If a bottle containing linseed oil be plunged in water with its mouth upwards, and open, the oil will ascent out of the bottle, and passing upwards through the mass of water, in a continued stream, will spread itself over its surface.

In like manner when two fluids of any kind, of different densities, come into contact, or are mixed with each other, that which is the lightest will be forced upwards by that which is the heaviest.

And as heat rarefies all bodies, fluids as well as solids, air as well as water, or mercury,--it follows that two portions of the same fluid, at different temperatures, being brought into contact with each other, that portion which is the hottest being more rarefied or specifically LIGHTER than that which is colder, must be forced upwards by this last.--And this is what always happens in fact.

When hot water and cold water are mixed, the hottest part of the mixture will be found to be at the surface above;--and when cold air is admitted into a warmed room, it will always be found to take its place at the bottom of the room, the warmer air being in part expelled, and in part forced upwards to the top of the room.

Both air and water being transparent and colourless fluids, their internal motions are not easily discovered by the sight, and when these motions are very slow, they make no impression whatever on any of our senses, consequently they cannot be detected by us without the aid of some mechanical contrivance:-- But where we have reason to think that those motions exist, means should be sought, and may often be found, for rendering them perceptible.

If a bottle containing hot water tinged with log-wood, or any other colouring drug, be immersed, with its mouth open, and upwards, into a deep glass jar filled with cold water, the ascent of the hot water from the bottle through the mass of cold water will be perfectly visible through the glass.-- Now nothing can be more evident than that both of these fluids are forced, or PUSHED, and not DRAWN upwards.--Smoke is frequently said to be drawn up the Chimney;--and that a Chimney draws well, or ill;--but these are careless expressions, and lead to very erroneous ideas respecting the cause of the ascent of Smoke; and consequently tend to prevent the progress of improvements in the management of fires.--The experiment just mentioned with the coloured water is very striking and beautiful, and it is well calculated to give a just idea of the cause of the ascent of Smoke. The cold water in the jar, which, in consequence of its superior weight or density, forces the heated and rarefied water in the bottle to give place to it, and to move upwards out of its way, may represent the cold air of the atmosphere, while the rising column of coloured water will represent the column of Smoke which ascends from a fire.

If Smoke required a Chimney to DRAW it upwards, how happens it that Smoke rises from a fire which is made in the open air, where there is no Chimney?

If a tube, open at both ends, and of such a length that its upper end be below the surface of the cold water in the jar, be held vertically over the mouth of the bottle which contains the hot coloured water, the hot water will rise up through it, just a smoke rises in a Chimney.

If the tube be previously heated before it is plunged into the cold water, the ascent of the hot coloured water will be facilitated and accelerated, in like manner as Smoke is known to rise with greater facility in a Chimney which is hot, than in one in which no fire has been made for a long time.--But in neither of these cases can it, with any propriety, be said, that the hot water is DRAWN up the tube.--The hotter the water in the bottle is, and the colder that in the jar, the greater will be the velocity with which the hot water will be forced up through the tube; and the same holds of the ascent of hot Smoke in a Chimney.--When the fire is intense, and the weather very cold, the ascent of the Smoke is very rapid; and under such circumstances Chimneys seldom smoke.

As the cold water of the jar immediately surrounding the bottle which contains the hot water, will be heated by the bottle while the other parts of the water in the jar will remain cold, this water so heated, becoming specifically lighter than that which surrounds it, will be forced upwards; and if it finds its way into the tube will rise up through it with the coloured hot water.--The warmed air of a room heated by an open Chimney Fire-place has always a tendency to rise, (if I may use that inaccurate expression,) and finding its way into the Chimney frequently goes off with the Smoke.

What has been said, will, I flatter myself, be sufficient to explain and illustrate, in a clear and satisfactory manner, the cause of the ascent of Smoke; and just ideas upon that subject are absolutely necessary in order to judge, with certainty, of the merit of any scheme proposed for the improvement of Fire-places; or to take effectual measures, in all cases, for curing smoking Chimnies.--For though the perpetual changes and alterations which are produced by accident, whim, and caprice, do sometimes lead to useful discoveries, yet the progress of improvement under such guidance must be exceedingly slow, fluctuating, and uncertain.

As to the causes of the smoking of Chimnies, they are very numerous, and various; but as a general idea of them may be acquired from what has already been said upon that subject in various parts of this Essay, and as they may, in all cases, (a very few only excepted,) be completely remedied by making the alterations in Fire-places here pointed out; I do not think it necessary to enumerate them all in this place, or to enter into those long details and investigations which would be required to show the precise manner in which each of them operates, either alone, or in conjunction with others.

There is however one cause of smoking Chimnies which I think it is necessary to mention more particularly.--In modern built houses, where the doors and windows are generally made to close with such accuracy that no crevice is left for the passage of the air from without, the Chimnies in rooms adjoining to each other, or connected by close passages, are frequently found to affect each other, and this is easy to be accounted for.--When there is a fire burning in one of the Chimnies, as the air necessary to supply the current up the Chimney where the fire burns cannot be had in sufficient quantities from without, through the very small crevices of the doors and windows, the air in the room becomes rarefied, not by heat, but by subtraction of that portion of air which is employed in keeping up the fire, or supporting the combustion of the fuel, and in consequence of this rarefaction, its elasticity is diminished, and being at last overcome by the pressure of the external air of the atmosphere, this external air rushes into the room by the only passage left for it, namely, by the open Chimney of the neighbouring room:--And the flow of air into the Fire-place, and up the Chimney where the fire is burning being constant, this expence of air is supplied by a continued current down the other Chimney.

If an attempt be made to light fires in both Chimnies at the same time, it will be found to be very difficult to get the fires to burn, and the rooms will both be filled with Smoke.

One of the fires,--that which is made in the Chimney where the construction of the Fire-place is best adapted to facilitate the ascent of the Smoke,--or if both Fire-places are on the same construction,--that which has the wind most favourable, or in which the fire happens to be soonest kindled,--will overcome the other, and cause its Smoke to be beat back into the room by the cold air which descends through the Chimney.--The most obvious remedy in this case is to provide for the supply of fresh air necessary for keeping up the fires by opening a passage for the external air into the room by a shorter road than down one of the Chimnies; and when this is done, both Chimnies will be found to be effectually cured.

But Chimnies so circumstanced may very frequently be prevented from smoking even without opening any new passage for the external air, merely by diminishing the draught, (as it is called,) up the Chimnies; which can best be done by altering both Fire-places upon the principles recommended and fully explained in the foregoing Chapters of this Essay.

Should the doors and windows of a room be closed with so much nicety as to leave no crevices by which a supply of air can enter sufficient for maintaining the fire, AFTER THE CURRENT OF AIR UP THE CHIMNEY HAS BEEN DIMINISHED AS MUCH AS POSSIBLE BY DIMINISHING THE THROAT OF THE FIRE-PLACE; in that case there would be no other way of preventing the Chimney from smoking but by opening a passage for the admission of fresh air from without;--but this, I believe, will very seldom be found to be the case.

A case more frequently to be met with is where currents of air set down Chimnies in consequence of a diminution and rarefaction of the air in a room, occasioned by the doors of the room opening into passages or courts where the air is rarefied by the action of some particular winds. In such cases the evil may be remedied, either by causing the doors in question to close more accurately,--or, (which will be still more effectual,) by giving a supply of air to the passage or court which wants it, by some other way.

Where the top of a Chimney is commanded by high buildings, by clifts, or by high grounds, it will frequently happen, in windy weather, that the eddies formed in the atmosphere by these obstacles will blow down the Chimney, and beat down the smoke into the room.--This it is true will be much less likely to happen when the throat of the Chimney is contracted and properly formed than when it is left quite open, and the Fire-place badly constructed; but as it is POSSIBLE that a Chimney may be so much exposed to these eddies in very high winds as to be made to smoke sometimes when the wind blows with violence from a certain quarter, it is necessary to show how the effects of those eddies may be prevented.

Various mechanical contrivances have been imagined for preventing the wind from blowing down Chimnies, and many of them have been found to be useful;--there are, however, many of these inventions, which, though they prevent the wind from blowing down the Chimney, are so ill-contrived on other accounts as to obstruct the ascent of the Smoke, and do more harm than good.

Of this description are all those Chimney-pots with flat horizontal plates or roofs placed upon supporters just above the opening of the pot;--and most of the caps which turn with the wind are not much better.--One of the most simple contrivances that can be made use of, and which in most cases will be found to answer the purpose intended as well or better than more complicated machinery, is to cover the top of the Chimney with a hollow truncated pyramid or cone, the diameter of which above, or opening for the passage of the Smoke, is about 10 or 11 inches. --This pyramid, or cone, (for either will answer,)--should be of earthen ware, or of cast iron;--its perpendicular height may be equal to the diameter of its opening above, and the diameter of its opening below equal to three times its height.--It should be placed upon the top of the Chimney, and it may be contrived so as to make a handsome finish to the brick-work.--Where several flews come out near each other, or in the same stack of Chimnies, the form of a pyramid will be better than that of a cone for these covers.

The intention of this contrivance is, that the winds and eddies which strike against the oblique surface of these covers may be reflected upwards instead of blowing down the Chimney.-- The invention is by no means new, but it has not hitherto been often put in practice.--As often as I have seen it tried it has been found to be of use; I cannot say, however, that I was ever obliged to have recourse to it, or to any similar contrivance; and if I forbear to enlarge upon the subject of these inventions, it is because I am persuaded that when Chimnies are properly constructed IN THE NEIGHBOURHOOD OF THE FIRE-PLACE little more will be necessary to be done at the top of the Chimney than to leave it open.

I cannot conclude this Essay without again recommending, in the strongest manner, a careful attention to the management of fires in open Chimnies; for not only the quantity of heat produced on the combustion of fuel depends much on the manner in which the fire is managed, but even of the heat actually generated a very small part only will be saved, or usefully employed, when the fire is made in a careless and slovenly manner.

In lighting a coal fire more wood should be employed than is commonly used, and fewer coals; and as soon as the fire burns bright, and the coals are well lighted, and NOT BEFORE, more coals should be added to increase the fire to its proper size[3].

The enormous waste of fuel in London may be estimated by the vast dark cloud which continually hangs over this great metropolis, and frequently overshadows the whole country, far and wide; for this dense cloud is certainly composed almost entirely of UNCONSUMED COAL, which having stolen wings from the innumerable fires of this great city has escaped by the Chimnies, and continues to sail about in the air, till having lost the heat which gave it volatility, it falls in a dry shower of extremely fine black dust to the ground, obscuring the atmosphere in its descent, and frequently changing the brightest day into more than Egyptian darkness.

I never view from a distance, as I come into town, this black cloud which hangs over London, without wishing to be able to compute the immense number of chaldrons of coals of which it is composed; for could this be ascertained, I am persuaded so striking a fact would awaken the curiosity, and excite the astonishment of all ranks of the inhabitants; and PERHAPS turn their minds to an object of economy to which they have hitherto paid little attention.

Conclusion.

Though the saving of fuel which will result from the improvements in the forms of CHIMNEY FIRE-PLACES here recommended will be very considerable, yet I hope to be able to show in a future Essay, that still greater savings may be made, and more important advantages derived from the introduction of improvements I shall propose in KITCHEN FIRE-PLACES.

I hope likewise to be able to show in an Essay on COTTAGE FIRE-PLACES, which I am now preparing for publication, that THREE QUARTERS, at least, of the fuel which cottagers now consume in cooking their victuals, and in warming their dwellings, may with great ease, and without any expensive apparatus, be saved.

END OF THE FOURTH ESSAY.

EXPLANATION OF THE FIGURES

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Fig. 1. The plan of a Fire-place on the common construction. A B, the opening of the Fire-place in front. C D, the back of the Fire-place. A C and B D, the covings. See page 341.

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Fig. 2. This figure shows the elevation, or front view of a Fire-place on the common construction. See page 341.

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Fig. 3. This Figure shows how the Fire-place represented by the Fig. 1, is to be altered in order to its being improved.

A B is the opening in front,--C D, the back, and A C and B D, the covings of the Fire-place in its original state.

a b, its opening in front,--i k, its back,--and a i and b k, its covings after it has been altered, e is a point upon the hearth upon which a plum suspended from the middle of the upper part of the breast of the Chimney falls. The situation for the new back is ascertained by taking the line e f equal to four inches. The new back and covings are represented as being built of bricks;--and the space between these and the old back and covings as being filled up with rubbish. See page 342.

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Fig. 4. This Figure represents the elevation or front view of the Fire-place Fig. 3. after it has been altered. The lower part of the door-way left for the Chimney-sweeper is shown in this Figure by white dotted lines. See page 344.

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Fig. 5. This Figure shows the section of a Chimney Fire-place and of a part of the canal of the Chimney, on the common construction.

a b is the opening in front; b c, the depth of the Fire-place at the hearth; d, the breast of the Chimney.

d e, the throat of the Chimney, and d f, g e, a part of the open canal of the Chimney.

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Fig. 6. Shows a section of the same Chimney after it has been altered.

k l is the new back of the Fire-place; l i, the tile or stone which closes the door-way for the Chimney-sweeper; d i, the throat of the Chimney, narrow to four inches; a, the mantle, and h, the new wall made under the mantle to diminish the height of the opening of the Fire-place in front.

N.B. These two Figures are sections of the same Chimney which is represented in each of the four preceding Figures.

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Fig. 7.

This Figure represents the ground plan of a Chimney Fire-place in which the grate is placed in a niche, and in which the original width A B of the Fire-place is considerably diminished.

a b is the opening of the Fire-place in front after it has been altered, and d is the back of the niche in which the grate is placed. See page 347.

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Fig. 8. Shows a front view of the same Fire-place after it has been altered; where may be seen the grate, and the door-way for the Chimney-sweeper. See page 347.

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Fig. 9. Shows a section of the same Fire-place, c d e being a section of the niche, g the door-way for the Chimney-sweeper, closed by a piece of the fire-stone, and f the new wall under the mantle by which the height of the opening of the Fire-place in front is diminished. See page 347.

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Fig. 10. This Figure shows how the covings are to be placed when the front of the covings (a and b) do not come so far forward as the front of the opening of the Fire-place, or the jambs (A and B). See page 348.

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Fig. 11. This Figure shows how the width and obliquity of the covings are to be accommodated to the width of the back of a Fire-place, in cases where it is necessary to make the back very wide. See page 349.

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Fig. 12. This Figure shows how an instrument called a bevel (m n), useful in laying out the work, in altering Chimney Fire-places, may be constructed. See page 349.

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Fig. 13. This shows how, when the breast of a Chimney (d) is too high, it may be brought down by means of a wall (h) placed under the mantle, and a coating of plaster, which in this Figure is represented by the part marked by dots. See page 351.

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Fig. 14. This shows how the breast of a Chimney may be brought down merely by a coating of plaster. See page 351.

Footnotes for essay IV.

[1] Eves and Sutton, bricklayers, Broad Sanctuary, Westminster, have alone altered above 90 Chimnies.--The experiment was first made in London at Lord Palmerston's house in Hanover-square;--then two Chimnies were altered in the house of Sir John Sinclair, Baronet, President of the Board of Agriculture; one in the room in which the Board meets, and the other in the Secretary's room; which last being much frequented by persons from all parts of Great Britain, it was hoped that circumstances would tend much to expedite the introduction of these improvements in various parts of the kingdom. Several Chimnies were altered in the house of Sir Joseph Banks, Baronet, K. B. President of the Royal Society. Afterwards a number were altered in Devonshire-house;--in the house of Earl Besborough, in Cavendish-square, and at his seat at Roehampton;--at Holywell-house, near St. Alban's, the seat of the Countess Dowager Spencer:--at Melbourne-house;--at Lady Templeton's in Portland-place; --at Mrs Montagu's in Portman-square;-- at Lord Sudley's, in Dover-street:--at the Marquis of Salisbury's seat at Hatfield, and at his house in town;--at Lord Palmerston's seat at Broadlands, near Southampton, and at several gentlemen's houses in that neighbourhood;--and a great many others; but it would be tiresome to enumerate them all; and even these are mentioned merely for the satisfaction of those who may wish to make inquiries respecting the success of the experiments.

[2] Having been obliged to carry backward the Fire-place in the manner here described, in order to accommodate it to a Chimney whose walls in front were remarkably thin,--I was surprised to find upon lighting the fire that it appeared to give out more heat into the room than any Fire-place I had ever constructed.-- This effect was quite unexpected; but the cause of it was too obvious not to be immediately discovered.--The flame rising from the fire broke against the part of the back which sloped forward over the fire, and this part of the back being soon very much heated, and in consequence of its being very hot, (and when the fire burnt bright it was frequently quite red hot,) it threw off into the room a great deal of radiant heat.--It is not possible that this oblique surface (the slope of the back of the Fire-place) could have been heated red-hot MERELY by the radiant heat projected by the burning fuel, for other parts of the Fire-place nearer the fire, and better situated for receiving radiant heat, were never found to be so much heated;--and hence it appears that the combined heat in the current of smoke and hot vapour which rises from an open fire MAY BE, at least IN PART, stopped in its passage up the Chimney, changing into radiant heat, and afterwards thrown into the room.--This opens up a new and very interesting field for experiment, and bids fair to lead to important improvements in the construction of Fire-places.--I have of late been much engaged in these investigations, and am now actually employed daily in making a variety of experiments with grates and Fire-places, upon different constructions, in the room I inhabit in the Royal Hotel in Pall Mall;--and Mr. Hopkins of Greek-street Soho, Ironmonger to his Majesty, and Mrs. Hempel, at her Pottery at Chelsea, are both at work in their different lines of business, under my direction, in the construction of Fire-places upon a principle entirely new, and which, I flatter myself, will be found to be not only elegant and convenient, but very economical.--But as I mean soon to publish a particular account of these Fire-places,--with drawings and ample directions for constructing them, I shall not enlarge farther on the subject in this place.--It may however not be amiss just to mention here, that these new-invented Fire-places not being fixed to the walls of the Chimney, but merely set down upon the hearth, may be used in any open Chimney: and that Chimnies altered or constructed on the principles here recommended are particularly well adapted for receiving them.

The Public in general, and more particularly those Tradesmen and Manufacturers whom it may concern, are requested to observe, that as the Author does not intent to take out himself, or to suffer others to take out, any patent for any invention of his which may be of public utility, all persons are at full liberty to imitate them, and vend them, for their own emolument, when and where, and in any way they may think proper; and those who may wish for any further information respecting any of those inventions or improvements will receive (gratis) all the information they can require by applying to the Author, who will take pleasure in giving them every assistance in his power.

[3] Kindling balls composed of equal parts of coal,--charcoal, --and clay, the two former reduced to a fine powder, well mixed and kneaded together with the clay moistened with water, and then formed into balls of the size of hens eggs, and thoroughly dried, might be used with great advantage instead of wood for kindling fires. These kindling balls may be made so inflammable as to take fire in an instant and with the smallest spark, by dipping them in a strong solution of nitre and then drying them again, and they would neither be expensive nor liable to be spoiled by long keeping. Perhaps a quantity of pure charcoal reduced to a very fine powder and mixed with the solution of nitre in which they are dipped would render them still more inflammable.

I have often wondered that no attempts should have been made to improve the fires which are made in the open Chimnies of elegant apartments, by preparing the fuel; for nothing surely was ever more dirty, inelegant, and disgusting than a common coal fire.

Fire balls of the size of goose eggs, composed of coal and charcoal in powder, mixed up with a due proportion of wet clay, and well dried, would make a much more cleanly, and in all respects a pleasanter fire than can be made with crude coals; and I believe would not be more expensive fuel. In Flanders and in several parts of Germany, and particular in the Dutchies of Juliers and Bergen, where coals are used as fuel, the coals are always prepared before they are used, by pounding them to a powder, and mixing them up with an equal weight of clay, and sufficient quantity of water to form the whole into a mass which is kneaded together and formed into cakes; which cakes are afterwards well dried and kept in a dry place for use. And it has been found by long experience that the expense attending this preparation is amply repaid by the improvement of the fuel. The coals, thus mixed with the clay, not only burn longer, but give much more heat than when they are burnt in their crude state.

It will doubtless appear extraordinary to those who have not considered the subject with some attention, that the quantity of heat produced in the combustion of any quantity of coals should be increased by mixing the coals with clay, which is certainly an incombustible body;--but the phenomenon may, I think, be explained in a satisfactory manner.

The heat generated in the combustion of any small particle of coal existing under two distinct forms, namely, in that which is COMBINED with the flame and smoke which rise from the fire, and which if means are not found to stop it, goes off immediately by the Chimney and is lost,--and the RADIANT HEAT which is sent off from the fire, in all directions in right lines:--I think it reasonable to conclude, that the particles of clay which are surrounded on all sides by the flame arrest a part at least of the combined heat, and prevent its escape; and this combined heat, so arrested, heating the clay red hot, is retained in it, and being changed by this operation to radiant heat, is afterwards emitted, and may be directed, and employed to useful purposes.

In composing fire balls, I think it probable that a certain proportion of chaff--of straw cut very fine, or even saw dust, might be employed with great advantage. I wish those who have leisure would turn their thoughts to this subject, for I am persuaded that very important improvements would result from a thorough investigation of it.

CONTENTS of ESSAY V.

A SHORT ACCOUNT of SEVERAL PUBLIC INSTITUTIONS Lately formed in Bavaria. together with the APPENDIX to the FIRST VOLUME.

Account I A Short Account of the military academy at munich

Account II An account of the means used to improve the bread of horses, and horned cattle, in Bavaria and the Palatinate.

Account III An account of the measures adopted for putting an end to usury at Munich.

Account IV An account of a scheme for employing the soldiery in Bavaria in repairing the highways and public roads.

APPENDIX

No. I Address and petition to all inhabitants and citizens of Munich, in the name of the real poor and distressed.

No. II
Subscription lists distributed among the inhabitants of Munich,
in the month of January 1790, when the establishment for the
relief of the poor in that city was formed.

No. III An account of the receipts and expenditures of the institution for the poor at Munich during five years.

No. IV Certificate relative to the expence of fuel in the public kitchen of the military workhouse at Munich.

No. V Printed form for the descriptions of the poor.

No. VI Printed form for spin-tickets, such as are used at the military workhouse at Munich.

No. VII An Account of experiments made at the bakehouse of the military workhouse at Munich, November the 4th and 5th, 1794.

No. VIII
Account of the persons in the house of industry in Dublin the
30th of April 1796, and of the details of the manner and expence
of feeding them.

No. IX
An account of an experiment made (under the direction of the
author,) in the kitchen of the house of industry at Dublin,
in cooking for the poor.

ESSAY V.

A short Account of the MILITARY ACADEMY at MUNICH.

Though it is certain that too much learning is rather disadvantageous than otherwise to the lower classes of the people;--that the introduction of a spirit of philosophical investigation,--literary amusement,--and metaphysical speculation among those who are destined by fortune to gain their livelihood by the sweat of their brow, rather tends to make them discontented and unhappy, than to contribute any thing to their real comfort and enjoyments; yet there appears, now and then, a native genius in the most humble stations, which it would be a pity not to be able to call forth into activity. It was principally with a view to bring forward such extraordinary talents, and to employ them usefully in the public service, that the Military Academy at Munich was instituted. This Academy, which consists of 180 eleves or pupils, is divided into three classes. The first class, which is designed for the education of orphans and other children of the poorer class of Military Officers, and those employed in the Civil Departments of the State, consists of thirty pupils, who are received gratis, from the age of eleven to thirteen years, and who remain in the Academy for years. The second class, which is designed to assist the poorer nobility, and less opulent among the merchants, citizens, and servants of government, in giving their sons a good general education, consists of sixty pupils, who are received from the age of eleven to fifteen years, and who pay to the Academy twelve florins a month; for which sum they are fed, clothed, and instructed. The third class, consisting of ninety pupils, from the age of fifteen to twenty years, who are all admitted gratis, is designed to bring forward such youths among the lower classes of the people as show evident signs of UNCOMMON TALENTS and genius, joined to a sound constitution of body, and a good moral character.

All Commanding Officers of regiments, and Public Officers in Civil departments, and all Civil Magistrates, are authorised and INVITED to recommend subjects for this class of the Academy, and they are not confined in their choice to any particular ranks of society, but they are allowed to recommend persons of the lowest extraction, and most obscure origin. Private soldiers, and the children of soldiers, and even the children of the meanest mechanics and day-labourers, are admissible, provided they possess the necessary requisites; namely, VERY EXTRAORDINARY NATURAL GENIUS, a healthy constitution, and a good character; but if the subject recommended should be found wanting in any of these requisite qualifications, he would not only be refused admittance into the Academy, but the person who recommended him would be very severely reprimanded.

The greatest severity is necessary upon these occasions, otherwise it would be impossible to prevent abuses. An establishment, designed for the encouragement of genius, and for calling forth into public utility talents which would otherwise remain buried and lost in obscurity, would soon become a job for providing for relations and dependants.

One circumstance, relative to the internal arrangement of this Academy, may, perhaps, be though not unworthy of being particularly mentioned, and that is the very moderate expence at which the institution is maintained. By a calculation, founded upon the experience of four years, I find that the whole Academy, consisting of 180 pupils, with professors and masters of every kind, servants, clothing, board, lodging, fire-wood, light, repairs, and every other article, house-rent alone excepted, amounts to no more than 28,000 florins a-year, which is no more than 155 florins, or about fourteen pounds sterling a-year for each pupil; a small sum indeed, considering the manner in which they are kept, and the education they receive.

Though this Academy is called a Military Academy, it is by no means confined to the education of those who are destined for the army; but it is rather an establishment of general education, where the youth are instructed in every science, and taught every bodily exercise, and personal accomplishment, which constitute a liberal education; and which fits them equally for the station of a private gentleman,--for the study of any of the learned professions,--or for any employment, civil or military, under the government.

As this institution is principally designed as a nursery for genius,--as a gymnasium for the formation of men,--for the formation of REAL MEN, possessed of strength and character, as well as talents and accomplishments, and capable of rendering essential service to the state; at all public examinations of the pupils, the heads of all the pupil departments are invited to be present, in order to witness the progress of the pupils, and to mark those who discover talents peculiarly useful in any particular departments or public employment.

How far the influence of this establishment may extend, time must discover. It has existed only six years; but even in that short period, we have had several instances of very uncommon talents having been called forth into public view, from the most obscure situations. I only wish that the institution may be allowed to subsist.

An Account of the Means used to improve the BREED of HORSE,
and HORNED CATTLE, in BAVARIA and the PALATINATE.

Through many parts of the Elector's dominions are well adapted for the breeding of fine horses, and great numbers of horses are actually bred[1]; yet no great attention had for many years been paid to the improvement of the breed; and most of the horses of distinction, such as were used by the nobility as saddle-horses and coach-horses, were imported from Holstein and Mecklenburg.

Being engaged in the arrangement of a new military system for the country, it occurred to me that, in providing horses for the use of the army, and particularly for the train of artillery, such measures might be adopted as would tend much to improve the breed of horses throughout the country; and my proposals meeting with the approbation of his Most Serene Electoral Highness, the plan was carried into execution in the following manner:

A number of fine mares were purchased with money take from the military chest, and being marked with an M (the initial of

Militaria), in a circle, upon the left hip, with a hot iron, they were given to such of the peasants, owning or leasing farms proper for breeding good horses, as applied for them. The conditions upon which these brood mares were given away were as follows:

They were, in the first place, given away gratis, and the person who received one of these mares is allowed to consider her as his own property, and use her in any kind of work he thinks proper; he is, however, obliged not only to keep her, and not to sell her, or give her away, but he is also under obligations to keep her as a brood mare, and to have her regularly covered every season, by a stallion pointed out to him by the commissioners, who are put at the head of this establishment. If she dies, he must replace her with another brood mare, which must be approved by the commissioners, and then marked.--If one of these mares should be found not to bring good colts, or to have any blemish, or essential fault or imperfection, she may be changed for another.

The stallions which are provided for these mares, and which are under the care of the commissioners, are provided gratis; and the foals are the sole property of those who keep the mares, and they may sell them, or dispose of them, when and where, and in any way they may think proper, in the same manner as they dispose of any other foal, brought by any other mare.

In case the army should be obliged to take the field, AND IN NO OTHER CASE WHATEVER, those who are in possession of these mares are obliged either to return them, or to furnish, for the use of the army, another horse fit for the service of the artillery.

The advantages of this arrangement to the army are obvious. In the case of an emergency, horses are always at hand, and these horses being bought in time of peace cost much less than it would be necessary to pay for them, were they to be purchased in a hurry upon the breaking out of a war, upon which occasions they are always dear, and sometimes not to be had for money.

It may perhaps be objected, that the money being laid out so long before the horses are wanted, the loss of the interest of the purchase-money ought to be taken into account; but as large sums of money must always be kept in readiness in the military chest, to enable the army to take the field suddenly, in case it should be necessary; and as a part of this money must be employed in the purchase of horses; it may as well be laid out beforehand, as to lie dead in the military chest till the horses are actually wanted; consequently the objection is not founded.

I wish I could say, that this measure had been completely successful; but I am obliged to own, that it has not answered my expectations. Six hundred mares only were at first ordered to be purchased and distributed; but I had hopes of seeing that number augmented soon to as many thousands; and I had even flattered myself with an idea of the possibility of placing in this manner among the peasants, and consequently having constantly in readiness, without any expence, a sufficient number of horses for the whole army; for the cavalry as well as for the artillery and baggage; and I had formed a plan for collecting together and exercising, every year, such of these horses as were destined for the service of the cavalry, and for permitting their riders to go on furlough with their horses: in short, my views went to the forming of an arrangement, very economical, and in many respects similar to that of the ancient feudal military system; but the obstinacy of the peasantry prevented these measures being carried into execution. Very few of them could be prevailed upon to accept of these horses; and in proportion as the terms upon which they were offered to them were apparently advantageous, their suspicions were increased, and they never would be persuaded that there was not some trick at the bottom of the scheme to over-reach them.

It is possible that their suspicions were not a little increased by the malicious insinuations of persons, who, from motives too obvious to require any explanation, took great pains at that time to render abortive every public undertaking in which I was engaged. But be that as it may, the fact is, I could never find means to remove these suspicions entirely, and I met with so much difficulty in carrying the measure into execution, that I was induced at last to abandon it, or rather to postpone its execution to a more favourable moment. Some few mares (two or three hundred) were placed in different parts of the country; and some very fine colts have been produced from them, during the six years that have elapsed since this institution was formed; but these slow advances do not satisfy the ardour of my zeal for improvement; and if means are not found to accelerate them, Bavaria, with all her natural advantages for breeding fine horses, must be obliged, for many years to come, to continue to import horses from foreign countries.

My attempts to improve the breed of horned cattle, though infinitely more confined, have been proportionally much more successful. Upon forming the public garden at Munich, as the extent of the grounds is very considerable, the garden being above six English miles in circumference, and the soil being remarkably good, I had an opportunity of making, within the garden, a very fine and a very valuable farm; and this farm being stocked with about thirty of the finest cows that could be procured from Switzerland, Flanders, Tyrol, and other places upon the Continent famous for a good breed of horned cattle; and this flock being refreshed annually with new importations of cows as well as bulls, all the cows which are produced, are distributed in the country, being sold to any person of the country who applies for them, AND WITH PROMISE TO REAR THEM, at the same low prices at which the most ordinary calves of the common breed of the country are sold to the butchers.

Though this establishment has existed only about six years, it is quite surprising what a change it has produced in the country. As there is a great resort to Munich from all parts of the country, it being the capital, and the residence of the Sovereign, the new English garden (as it is called), which begins upon the ramparts of the town, and extends near two English miles in length, and is always kept open, is much frequented, and there are few who go into the garden without paying a visit to the cows, which are always at home. Their stables, which are concealed in a thick wood behind a public coffee-house or tavern in the middle of the garden, are elegantly fitted up and kept with great care; and the cows, which are not only large, and remarkably beautiful, but are always kept perfectly clean, and in the highest condition, are an object of public curiosity. Those who are not particularly interested in the improvement of cattle, go to see them as beautiful and extraordinary animals; but farmers and connoisseurs go to EXAMINE them,--to compare them with each other,--and with the common breed of the country, and to get information with respect to the manner of feeding them, and the profits derived from them; and so rapidly has the flame of improvement spread throughout every part of Bavaria from this small spark, that I have no doubt but in a very few years the breed of horned cattle will be quite changed.

Not satisfied with the scanty supply furnished from the farm in the English garden, several of the nobility, and some of the most wealthy and enterprising of the farmers, are sending to Switzerland, and other distant countries famous for fine cattle, for cows and bulls; and the good effects of these exertions are already visible in many parts of the country.

How very easy would it be by similar means to introduce a spirit of improvement in any country! and where sovereigns do not make public gardens to bring together a concourse of people, individuals might do it by private subscription, or at least they might unite together and rent a large farm in the neighbourhood of the capital, for the purpose of making useful experiments. If such a farm were well managed, the produce of it would be more than sufficient to pay all the expenses attending it; and if the grounds and fields were laid out with taste--if good roads for carriages and for those who ride on horseback were made round it, and between all the fields--if the stables were elegantly fitted up--filled with beautiful cattle, kept perfectly clean and neat; and if a handsome inn were erected near the buildings of the farm, where those who visited it might be furnished with refreshment, it would soon become a place of public resort and improvements in agriculture would become A FASHIONABLE AMUSEMENT; the ladies even would take pleasure in viewing from their carriages the busy and most interesting scenes of rural industry, and it would no longer be thought vulgar to understand the mysteries of Ceres.

Why should not Parliament purchase, or rent such a farm in the neighbourhood of London, and put it under the direction of the Board of Agriculture? The expence would be but a mere trifle, if any thing, and the institution would not only be useful, but extremely interesting; and it would be an inexhaustible source of rational and innocent amusement, as well as of improvement to vast numbers of the most respectable inhabitants of this great metropolis.

In former times, statesmen considered the amusement of the public as an object of considerable importance, and pains were taken to render the public amusements useful in forming the national character.

An Account of the Measures adopted for putting an End to USURY
at MUNICH.

Another measure, more limited in its operations than those before mentioned, but which notwithstanding was productive of much good, was adopted, in which a part of the treasure which was lying dead in the military chest was usefully employed for the relief of a considerable number of individuals, employed in subordinate stations under the government, who stood in great need of assistance.