ESSAYS, Political, Economical and Philosophical. Volume 1.
by
Benjamin Rumford
Part 5 out of 7
This makes an excellent and a very wholesome dish, but more
calculated, it is true, for the tables of the opulent than for
the Poor.--Good sauces might however be composed for this dish
which would not be expensive.--Common milk-porridge, made rather
thicker than usual, with wheat flour, and well salted, would not
be a bad sauce for it.
Potatoe Salad.
A dish in high repute in some parts of Germany, and which
deserves to be particularly recommended, is a salad of potatoes.
The potatoes being properly boiled and skinned, are cut into thin
slices, and the same sauce which is commonly used for salads of
lettuce is poured over them; some mix anchovies with this sauce,
which gives it a very agreeable relish, and with potatoes it is
remarkably palatable.
Boiled potatoes cut in slices and fried in butter, or in lard,
and seasoned with salt and pepper, is likewise a very palatable
and wholesome dish.
Of Barley.
I have more than once mentioned the extraordinary nutritive
powers of this grain, and the use of it in feeding the Poor
cannot be too strongly recommended.--It is now beginning to be
much used in this country, mixed with wheat flour, for making
bread; but is not, I am persuaded, in bread, but in soups,
that Barley can be employed to the greatest advantage.--It is
astonishing how much water a small quantity of Barley-meal will
thicken, and change to the consistency of a jelly; and, if my
suspicions with regard to the part which water acts in nutrition
are founded, this will enable us to account, not only for the
nutritive quality of Barley, but also for the same quality in a
still higher degree which sago and salope are known to possess.--
Sago and Salope thicken, and change to the consistency of a
jelly, (and as I suppose, prepare for decomposition,) a greater
quantity of water than Barley, and both sago and salope are known
to be nutritious in a very extraordinary degree.
Barley will thicken and change to a jelly much more water than
any other grain with which we are acquainted, rice even not
excepted;--and I have found reason to conclude from the result of
innumerable experiments, which in the course of several years
have been made under my direction in the public kitchen of the
House of Industry at Munich, that for making soups, Barley is by
far the best grain that can be employed.
Were I called upon to give an opinion in regard to the
comparative nutritiousness of Barley-meal and wheat flour,
WHEN USED IN SOUPS I should not hesitate to say that I think the
former at least three or four times as nutritious as the latter.
Scotch broth is known to be one of the most nourishing dishes in
common use; and there is no doubt but it owes its extraordinary
nutritive quality to the Scotch (or Pearl) Barley, which is
always used in preparing it.--If the Barley be omitted, the broth
will be found to be poor and washy, and will afford little
nourishment;--but any of the other ingredients may be retrenched;--
even the meat;-- without impairing very sensibly the nutritive
quality of the Food.--Its flavour and palatableness may be impaired
by such retrenchments; but if the water be well thickened with
the Barley, the Food will still be very nourishing.
In preparing the soup used in feeding the Poor in the House of
Industry at Munich, Pearl Barley has hitherto been used; but I
have found, by some experiments I have lately made in London,
that Pearl Barley is by no means necessary, as common Barley-meal
will answer, to all intents and purposes, just as well.--In one
respect it answers better, for it does not require half so much
boiling.
In comparing cheap soups for feeding the Poor, the following
short and plain directions will be found to be useful:
General Directions for preparing cheap Soup.
First, Each portion of Soup should consist of one pint and a
quarter, which, if the Soup be rich, will afford a good meal to a
grown person.--Such a portion will in general weigh about one
pound and a quarter, or twenty ounces Avoirdupois.
Secondly, The basis of each portion of Soup should consist of one
ounce and a quarter of Barley-meal, boiled with ONE PINT AND A
QUARTER OF WATER till the whole be reduced to the uniform
consistency of a thick jelly.--All other additions to the Soup do
little else than to serve to make it more palatable; or by
rendering a long mastication necessary, to increase and prolong
the pleasure of eating;--both these objects are however of very
great importance, and too much attention cannot be paid to them;
but both of them may, with proper management, be attained without
much expence.
Were I asked to give a Receipt for the cheapest Food which
(in my opinion) it would be possible to provide in this country,
it would be the following:
Receipt for a very cheap Soup.
Take of water eight gallons, and mixing with it 5 lb. of Barley-meal,
boil it to the consistency of a thick jelly.--Season it with
salt, pepper, vinegar, sweet herbs, and four red herrings,
pounded in a mortar.--Instead of bread, add to it 5 lb. of Indian
Corn made into Samp, and stirring it together with a ladle, serve
it up immediately in portions of 20 ounces.
Samp, which is here recommended, is a dish said to have been
invented by the savages of North America, who have no Corn-mills.
--It is Indian Corn deprived of its external coat by soaking it
ten or twelve hours in a lixivium of water and wood-ashes.--
This coat, or husk, being separated from the kernel, rises to the
surface of the water, while the grain, which is specifically
heavier than water, remains at the bottom of the vessel; which
grain, thus deprived of its hard coat of armour, is boiled, or
rather simmered for a great length of time, two days for instance,
in a kettle of water placed near the fire.--When sufficiently
cooked, the kernels will be found to be swelled to a great size
and burst open, and this Food, which is uncommonly sweet and
nourishing, may be used in a great variety of ways; but the best
way of using it is to mix it with milk, and with soups, and broths,
as a substitute for bread. It is even better than bread for
these purposes, for besides being quite as palatable as the very
best bread, as it is less liable than bread to grow too soft when
mixed with these liquids, without being disagreeably hard, it
requires more mastication, and consequently tends more to increase
and prolong the pleasure of eating.
The Soup which may be prepared with the quantities of ingredients
mentioned in the foregoing Receipt will be sufficient for 64
portions, and the cost of these ingredients will be as follows:
Pence.
For 5 lb. of Barley-meal, at 1 1/2 pence, the ]
Barley being reckoned at the present ]
very high price of it in this country, viz ]... 7 1/2
5s. 6d. per bushel ]
5 lb. of Indian Corn, at 1 1/4 pence the pound ... 6 1/4
4 red herrings ... ... ... ... ... ... ... 3
Vinegar... ... ... ... ... ... ... ... ... 1
Salt ... ... ... ... ... ... ... ... ... 1
Pepper and sweet herbs ... ... ... ... ... 2
-------
Total 20 3/4
-------
This sum, (20 3/4 pence,) divided by 64, the number of portions
of Soup, gives something less than ONE THIRD OF A PENNY for the
cost of each portion.--But at the medium price of Barley in Great
Britain, and of Indian Corn as it may be afforded here, I am
persuaded that this Soup may be provided at one farthing the
portion of 20 ounces.
There is another kind of Soup in great repute among the poor
people, and indeed among the opulent farmers, in Germany, which
would not come much higher.--This is what is called burnt Soup,
or as I should rather call it, brown Soup, and it is prepared in
the following manner:
Receipt for making BROWN SOUP.
Take a small piece of butter and put it over the fire in a clean
frying-pan made of iron (not copper, for that metal used for this
purpose would be poisonous);-- put to it a few spoonfuls of wheat
or rye meal;--stir the whole about briskly with a broad wooden
spoon, or rather knife, with a broad and thin edge, till the
butter has disappeared, and the meal is uniformly of a deep brown
colour; great care being taken, by stirring it continually, to
prevent the meal from being burned to the pan.
A very small quantity of this roasted meal, (perhaps half an
ounce in weight would be sufficient,) being put into a sauce-pan
and boiled with a pint and a quarter of water, forms a portion of
Soup, which, when seasoned with salt, pepper, and vinegar, and
eaten with bread cut fine, and mixed with it at the moment when
it is served up, makes a kind of Food by no means unpalatable;
and which is said to be very wholesome.
As this Soup may be prepared in a very short time, an instant
being sufficient for boiling it; and as the ingredients for
making it are very cheap, and may be easily transported,
this Food is much used in Bavaria by our wood-cutters, who go
into the mountains far from any habitations to fell wood.--
Their provisions for a week, (the time they commonly remain in
the mountains,) consist of a large loaf of rye bread (which,
as it does not so soon grow dry and stale as wheaten bread,
is always preferred to it); a linen bag containing a small
quantity of roasted meal;--another small bag of salt;--and a
small wooden box containing some pounded black pepper;--with a
small frying-pan of hammered iron, about ten or eleven inches in
diameter, which serves them both as an utensil for cooking, and
as a dish for containing the victuals when cooked.--They
sometimes, but not often, take with them a small bottle of
vinegar;--but black-pepper is an ingredient in brown Soup which
is never omitted.--Two table-spoonfuls of roasted meal is quite
enough to make a good portion of Soup for one person; and the
quantity of butter necessary to be used in roasting this quantity
of meal is very small, and will cost very little.--One ounce of
butter would be sufficient for roasting eight ounces of meal; and
if half an ounce of roasted meal is sufficient for making one
portion of Soup, the butter will not amount to more than 1/10 of
an ounce; and, at eight pence the pound, will cost only 1/32 of a
penny, or 1/8 of a farthing.--The cost of the meal for a portion
of this Soup is not much more considerable. If it be rye meal,
(which is said to be quite as good for roasting as the finest
wheat flour,) it will not cost, in this country, even now when
grain is so dear, more than 1 1/2d. per pound;-- 1/2 an ounce,
therefore, the quantity required for one portion of the Soup,
would cost only 6/32 of a farthing;--and the meal and butter
together no more than (1/8 + 6/32) = 10/32, or something less
than 1/3 of a farthing.--If to this sum we add the cost of the
ingredients used to season the Soup, namely, for salt, pepper and
vinegar, allowing for them as much as the amount of the cost of
the butter and the meal, or 1/3 of a farthing, this will give 2/3
of a farthing for the cost of the ingredients used in preparing
one portion of this Soup; but as the bread which is eaten with it
is an expensive article, this Food will not, upon the whole,
be cheaper than the Soup just mentioned; and it is certainly
neither so nourishing nor so wholesome.
Brown Soup might, however, on certain occasions, be found to be
useful. As it is so soon cooked, and as the ingredients for
making it are so easily prepared, preserved, and transported from
place to place; it might be useful to travellers, and to soldiers
on a march. And though it can hardly be supposed to be of itself
very nourishing, yet it is possible it may render the bread eaten
with it not only more nutritive, but also more wholesome;-- and
it certainly renders it more savoury and palatable.--It is the
common breakfast of the peasants in Bavaria; and it is infinitely
preferable, in all respects, to that most pernicious wash, TEA,
with which the lower classes of the inhabitants of this island
drench their stomachs, and ruin their constitutions.
When tea is mixed with a sufficient quantity of sugar and good
cream;--when it is taken with a large quantity of bread and
butter, or with toast and boiled eggs;--and above all,--WHEN IT
IS NOT DRANK TOO HOT, it is certainly less unwholesome; but a
simple infusion of this drug, drank boiling hot, as the Poor
usually take it, is certainly a poison which, though it is
sometimes slow in its operation, never fails to produce very
fatal effects, even in the strongest constitution, where the free
use of it is continued for a considerable length of time.
Of Rye Bread
The prejudice in this island against bread made of Rye, is the
more extraordinary, as in many parts of the country no other kind
of bread is used; and as the general use of it in many parts of
Europe, for ages, has proved it to be perfectly wholesome.--
In those countries where it is in common use, many persons
prefer it to bread made of the best wheat flour; and though
wheaten bread is commonly preferred to it, yet I am persuaded
that the general dislike of it, where it is not much in use, is
more owing to its being BADLY PREPARED, or not well baked, than
to any thing else.
As an account of some experiments upon baking Rye Bread, which
were made under my immediate care and inspection in the
bake-house of the House of Industry at Munich, may perhaps be of
use to those who wish to known how good Rye Bread may be prepared;
as also to such as are desirous of ascertaining, by similar
experiments, what, in any given case, the profits of a baker
really are; I shall publish an account in detail of these
experiments, in the Appendix to this volume.
I cannot conclude this Essay, without once more recommending,
in the most earnest manner, to the attention of the Public,
and more especially to the attention of all those who are engaged
in public affairs,--the subject which has here been attempted to
be investigated. It is certainly of very great importance,
in whatever light it is considered; and it is particularly so at
the present moment: for however statesmen may differ in opinion
with respect to the danger or expediency of making any alterations
in the constitution, or established forms of government, in times
of popular commotion, no doubts can be entertained with respect
to the policy of diminishing, as much as possible, at all times,
--and more especially in times like the present,--the misery of
the lower classes of the people.
END OF THE THIRD ESSAY.
Footnotes for Essay III.
[1]
November 1795.
[2]
The preparation of water is, in many cases, an object of more
importance than is generally imagined; particularly when it is
made use of as a vehicle for conveying agreeable tastes.
In making punch, for instance, if the water used be previously
boiled two or three hours with a handful of rice, the punch made
from it will be incomparably better, than is to say, more full
and luscious upon the palate, than when the water is not prepared.
[3]
I cannot dismiss this subject, the feeding of cattle, without
just mentioning another practice common among our best farmers in
Bavaria, which, I think, deserves to be known. They chop the
green clover with which they feed their cattle, and mix with it a
considerable quantity of chopped straw. They pretend that this
rich succulent grass is of so clammy a nature, that unless it be
mixed with chopped straw, hay, or some other dry fodder, cattle
which are fed with it do not ruminate sufficiently. The usual
proportion of the clover to the straw, is as two to one.
[4]
A viertl is the twelfth part of a schafl, and the Bavarian schafl
is equal to 6 31/300 Winchester bushels.
[5]
The quantity of fuel here mentioned, though it certainly is
almost incredibly small, was nevertheless determined from the
results of actual experiments. A particular account of these
experiments will be given in my Essay on the Management of Heat
and the Economy of Fuel.
[6]
One Bavarian schafl (equal to 6 31/100 Winchester bushels) of
barley, weighing at a medium 250 Bavarian pounds, upon being
pearled, or rolled (as it is called in Germany), is reduced to
half a schafl, which weighs 171 Bavarian pounds. The 79lb. which
it loses in the operation is the perquisite of the miller, and is
all he receives for his trouble.
[7]
Since the First Edition of this Essay was published the experiment
with barley-meal has been tried, and the meal has been found to
answer quite as well as pearl barley, if not better, for making
these soups. Among others, Thomas Bernard, Esq. Treasurer of
the Founding Hospital, a gentleman of most respectable character,
and well known for his philanthropy and active zeal in relieving
the distresses of the Poor, has given it a very complete and fair
trial; and he found, what is very remarkable, though not difficult
to be accounted for--that the barley-meal, WITH ALL THE BRAN IN IT,
answered better, that is to say, made the soup richer, and thicker,
than when the fine flour of barley, without the bran, was used.
[8]
By some experiments lately made it has been found that the soup
will be much improved if a small fire is made under the boiler,
just sufficient to make its contents boil up once, when the
barley and water are put into it, and then closing up immediately
the ash-hole register, and the damper in the chimney,
and throwing a thick blanket, or a warm covering over the cover
of the boiler, the whole be kept hot till the next morning.
This heat so long continued, acts very powerfully on the barley,
and causes it to thicken the water in a very surprising manner.
Perhaps the oat-meal used for making water gruel might be
improved in its effects by the same means. The experiment is
certainly worth trying.
[9]
This invention of double bottoms might be used with great success
by distillers, to prevent their liquor, when it is thick, from
burning to the bottoms of their stills. But there is another
hint, which I have long wished to give distillers, from which,
I am persuaded, they might derive very essential advantages.--It is
to recommend to them to make up warm clothing of thick blanketing
for covering up their still-heads, and defending them from the
cold air of the atmosphere; and for covering in the same manner
all that part of the copper or boiler which rises above the
brick-work in which it is fixed. The great quantity of heat is
constantly given off to the cold air of the atmosphere in contact
with it by this naked copper, not only occasions a very great
loss of heat, and of fuel, but tends likewise very much to
EMBARRASS and to PROLONG the process of distillation; for all
the heat communicated by the naked still-head to the atmosphere
is taken from the spirituous vapour which rises from the liquor
in the still; and as this vapour cannot fail to be condensed into
spirits whenever and WHEREVER it loses ANY PART of its heat,--
as the spirits generated in the still-head in consequence of this
communication of heat to the atmosphere do not find their way
into the worm, but trickle down and mix again with the liquor in
the still,--the bad effects of leaving the still-head exposed
naked to the cold air is quite evident. The remedy for this evil
is as cheap and as effectual, as it is simple and obvious.
[10]
The Bavarian pound (equal to 1.238, or near one pound and a
quarter Avoirdupois,) is divided into 32 loths.
[11]
For each 100 lb. Bavarian weight, (equal to 123.84 lb.
Avoirdupois,) of rye-meal, which the baker receives from the
magazine, he is obliged to deliver sixty-four loaves of bread,
each loaf weighing 2 lb. 5 1/2 loths; equal to 2 lb. 10 oz.
Avoirdupois;--and as each loaf is divided into six portions,
this gives seven ounces Avoirdupois for each portion. Hence it
appears that 100 lb. of rye-meal give 149 lb. of bread; for
sixty-four loaves, at 2 lb. 5 1/2 loths each, weigh 149 lb.
--When this bread is reckoned at two creutzers a Bavarian pound,
(which is about what it costs at a medium,) one portion costs
just 10/16 of a creutzer, or 120/528 of a penny sterling, which
is something less than one farthing.
[12]
This allowance is evidently much too large; but I was willing to
show what the expence of feed the Poor would be at THE HIGHEST
CALCULATION. I have estimated the 7 ounces of rye-bread,
mentioned above, at what it ought to cost when rye is 7s. 6d. the
bushel, its present price in London.
[13]
Farther inquiries which have since been made, have proved that
these suspicions were not without foundation.
[14]
Since writing the above, I have had an opportunity of ascertaining,
in the most decisive and satisfactory manner, the facts relative
to the weight of Indian Corn of the growth of the northern states
of America. A friend of mine, an American gentleman, resident in
London, (George Erving, Esq. of Great George street, Hanover-square,)
who, in common with the rest of his countrymen, still retains a
liking for Indian Corn, and imports it regularly every year from
America, has just received a fresh supply of it, by one of the
last ships which has arrived from Boston in New England; and at
my desire he weighed a bushel of it, and found it to weigh 61 lb.:
It cost him at Boston three shillings and sixpence sterling the
bushel.
[15]
The price of Indian meal as it here estimated,--(2d. a pound,)
--is at least twice as much as it would cost in Great Britain in
common years, if care was taken to import it at the cheapest rate.
[16]
Those who dislike trouble, and feel themselves called upon by
duty and honor to take an active part in undertakings for the
public good, are extremely apt to endeavour to excuse,--to
themselves as well as to the world,--their inactivity and
supineness, by representing the undertaking in question as being
so very difficult as to make all hope of success quite chimerical
and ridiculous.
[17]
The Housekeeper of my friend and countryman, Sir William Pepperel,
Bart. of Upper Seymour Street, Portman Square.
[18]
Molasses imported from the French West India Islands into the
American States is commonly sold there from 12d. to 14d.
the gallon.
[19]
This gentleman, who is as remarkable for his good fortune at sea,
as he is respectable on account of his private character and
professional knowledge, has crossed the Atlantic Ocean the almost
incredible number of ONE HUNDRED AND TEN TIMES! and without
meeting with the smallest accident. He is now on the seas in his
way to North America; and this voyage, which is his HUNDRED AND
ELEVENTH, he intends should be his last. May he arrive
safe,--and may he long enjoy in peace and quite the well-earned
fruits of his laborious life! Who can reflect on the innumerable
storms he must have experienced, and perils he has escaped,
without feeling much interested in his preservation and
happiness?
[20]
This maccaroni would not probably have cost one quarter of that
sum at Naples.--Common maccaroni is frequently sold there as low
as fourteen grains, equal to five pence halfpenny sterling the
rottolo, weighing twenty-eight ounces and three quarters
Avoirdupois, which is three pence sterling the pound Avoirdupois.
An inferiour kind of maccaroni, such as is commonly sold at
Naples to the Poor, costs not more than two pence sterling the
pound Avoirdupois.
[21]
If maccaroni could be made in this country as cheap as it is made
in Naples, that is to say, so as to be afforded for three pence
sterling the pound Avoirdupois, for the best sort, (and I do not
see why it should not,) as half a pound of dry maccaroni weighs
when boiled very nearly two pounds, each pound of boiled
maccaroni would cost only three farthings, and the cheese
necessary for giving it a relish one farthing more, making
together one penny; which is certainly a very moderate price for
such good and wholesome Food.
CONTENTS of ESSAY IV.
of CHIMNEY FIRE-PLACES, with PROPOSALS for improving them to save
FUEL; to render dwelling-houses more COMFORTABLE and SALUBRIOUS,
and effectually to prevent CHIMNIES from SMOKING.
ADVERTISEMENT
CHAPTER. I.
Fire-places for burning coals, or wood, in an open chimney,
are capable of great improvement.
Smoking chimnies may in all cases be completely cured.
The immoderate size of the throats of chimnies the principal
cause of all their imperfections.
Philosophical investigation of the subject.
Remedies proposed for all the defects that have been discovered
in chimnies and their open fire-places.
These remedies applicable to chimnies destined for burning
wood, or turf, as well as those constructed for burning coals.
CHAPTER. II.
Practical directions designed for the use of workmen, showing
how they are to proceed in making the alterations necessary to
improve chimney fire-places, and effectually to cure smoking
chimnies.
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.
ESSAY IV.
ADVERTISEMENT
The Author thinks it his duty to explain the reasons which have
induced him to change the order in which the publication of his
Essays has been announced to the Public.--Being suddenly called
upon to send to Edinburgh a person acquainted with the method of
altering Chimney Fire-places, which has lately been carried into
execution in a number of houses in London, in order to introduce
these improvements in Scotland, he did not think it prudent to
send any person on so important an errand without more ample
instruction than could well be given verbally; and being obliged
to write on the subject, he thought it best to investigate the
matter thoroughly, and to publish such particular directions
respecting the improvements in question as may be sufficient to
enable all those, who may be desirous of adopting them, to make,
or direct the necessary alterations in their Fire-places without
any further assistance.
The following Letter, which the Author received from Sir John
Sinclair, Baronet, Member of Parliament, and President of the
Board of Agriculture, will explain this matter more fully:
You will hear with pleasure that your mode of altering Chimnies,
so as to prevent their smoking, to save fuel, and to augment
heat, has answered not only with me, but with many of my friends
who have tried it; and that the Lord Provest and Magistrates of
Edinburgh have voted a sum of money to defray the expences of a
bricklayer, who is to be sent there for the purpose of
establishing the same plan in that city. I hope that you will
have the goodness to expedite your paper upon the management of
Heat, that the knowledge of so useful an art may be as rapidly
and as extensively diffused as possible.--With my best wishes for
your success in the various important pursuits in which you are
now engaged, believe me, with great truth and regard,
Your faithful and obedient servant
John Sinclair
Whitehall, London,
9th February 1796.
CHAPTER. I.
Fire-places for burning coals, or wood, in an open chimney,
are capable of great improvement.
Smoking chimnies may in all cases be completely cured.
The immoderate size of the throats of chimnies the principal
cause of all their imperfections.
Philosophical investigation of the subject.
Remedies proposed for all the defects that have been discovered
in chimnies and their open fire-places.
These remedies applicable to chimnies destined for burning
wood, or turf, as well as those constructed for burning coals.
The plague of a smoking Chimney is proverbial; but there are many
other very great defects in open Fire-places, as they are now
commonly constructed in this country, and indeed throughout
Europe, which, being less obvious, are seldom attended to;
and there are some of them very fatal in their consequences to
health; and, I am persuaded, cost the lives of thousands every
year in this island.
Those cold and chilling draughts of air on one side of the body,
while the other side is scorched by a Chimney Fire, which every
one who reads this must often have felt, cannot but be highly
detrimental to health; and in weak and delicate constitutions
must often produce the most fatal effects.--I have not a doubt in
my own mind that thousands die in this country every year of
consumptions occasioned solely by this cause.--By a cause which
might be so easily removed!--by a cause whose removal would tend
to promote comfort and convenience in so many ways.
Strongly impressed as my mind is with the importance of this
subject, it is not possible for me to remain silent.--The subject
is too nearly connected with many of the most essential
enjoyments of life not to be highly interesting to all those who
feel pleasure in promoting, or in contemplating the comfort and
happiness of mankind.--And without suffering myself to be
deterred, either by the fear of being thought to give the subject
a degree of importance to which it is not entitled, or by the
apprehension of being tiresome to my readers by the prolixity of
my descriptions,--I shall proceed to investigate the subject in
all its parts and details with the utmost care and attention.
--And first with regard to smoking Chimnies:
There are various causes by which Chimnies may be prevented from
carrying smoke; but there are none that may not easily be
discovered and completely removed.--This will doubtless be
considered as a bold assertion; but I trust I shall be able to
make it appear in a manner perfectly satisfactory to my readers
that I have not ventured to give this opinion but upon good and
sufficient grounds.
Those who will take the trouble to consider the nature and
properties of elastic fluids,--of air,--smoke,--and vapour,--
and to examine the laws of their motions, and the necessary
consequences of their being rarified by heat, will perceive that
it would be as much a miracle if smoke should not rise in a
Chimney, (all hindrances to its ascent being removed,) as that
water should refuse to run in a syphon, or to descend in a river.
The whole mystery, therefore, of curing smoking Chimnies is
comprised in this simple direction. --FIND OUT AND REMOVE THOSE
LOCAL HINDRANCES WHICH FORCIBLY PREVENT THE SMOKE FROM FOLLOWING
ITS NATURAL TENDENCY TO GO UP THE CHIMNEY; or rather, to speak
more accurately, which prevents its being forced up the Chimney
by the pressure of the heavier air of the room.
Although the causes, by which the ascent of smoke in a Chimney
MAY BE obstructed, are various, yet that cause which will most
commonly, and I may say almost universally be found to operate,
is one which it is always very easy to discover, and as easy to
remove,--the bad construction of the Chimney IN THE NEIGHBOURHOOD
OF THE FIRE-PLACE.
In the course all my experience and practice in curing smoking
Chimnies,--and I certainly have not had less than five hundred
under my hands, and among them many which were thought to be
quite incurable,--I have never been obliged, except in one
single instance, to have recourse to any other method of cure
than merely reducing the Fire-place and the throat of the
Chimney, or that part of it which lies immediately above the
Fire-place, to a proper form, and just dimensions.
That my principles for constructing Fire-places are equally
applicable to those which are designed for burning coal, as to
those in which wood is burnt, has lately been abundantly proved
by experiments made here in London; for of above an hundred and
fifty Fire-places which have been altered in this city, under my
direction, within these last two months, there is not one which
has not answered perfectly well[1].--And by several experiments
which have been made with great care, and with the assistance of
thermometers, it has been demonstrated, that the saving of fuel,
arising from these improvements of Fire-places, amounts in all
cases to more than HALF, and in many cases to more than TWO THIRDS
of the quantity formerly consumed.--Now as the alterations in
Fire-places which are necessary may be made at a very trifling
expence, as any kind of grate or stove may be made use of, and as
no iron work, but merely a few bricks and some mortar, or a few
small pieces of fire-stone, are required; the improvement in
question is very important, when considered merely with a view
to economy; but it should be remembered, that not only a great
saving is made of fuel by the alterations proposed, but that
rooms are made much more comfortable, and more salubrious;--
that they may be more equally warmed, and more easily kept at any
required temperature;--that all draughts of cold air from the
doors and windows towards the Fire-place, which are so fatal to
delicate constitutions, will be completely prevented;--that in
consequence of the air being equally warm all over the room, or
in all parts of it, it may be entirely changed with the greatest
facility, and the room completely ventilated, when this air is
become unfit for respiration, and this merely by throwing open
for a moment a door opening into some passage from whence fresh
air may be had, and the upper part of a window; or by opening the
upper part of on window and the lower part of another, and as the
operation of ventilating the room, even when it is done in the
most complete manner, will never require the door and window to
be open more than one minute; in this short time the walls of the
room will not be sensibly cooled, and the fresh air which comes
into the room will, in a very few minutes, be so completely
warmed by these walls that the temperature of the room, though
the air in it be perfectly changed, will be brought to be very
nearly the same as it was before the ventilation.
Those who are acquainted with the principles of pneumatics,
and know why the warm air in a room rushes out at an opening made
for it at the top of a window when colder air from without is
permitted to enter by the door, or by any other opening situated
lower than the first, will see, that it would be quite impossible
to ventilate a room in the complete and expeditious manner here
described, where the air in a room is partially warmed, or hardly
warmed at all, and where the walls of the room, remote from the
fire, are constantly cold; which must always be the case where,
in consequence of a strong current up the Chimney, streams of
cold air are continually coming in through all the crevices of
the doors and windows, and flowing into the Fire-place.
But although rooms, furnished with Fire-places constructed upon
the principles here recommended, may be easily and most
effectually ventilated, (and this is certainly a circumstance in
favour of the proposed improvements,) yet such total ventilations
will very seldom, if ever, be necessary.--As long as ANY FIRE is
kept up in the room, there is so considerable a current of air up
the Chimney, notwithstanding all the reduction that can be made
in the size of its throat, that the continual change of air in
the room which this current occasions will, generally, be found
to be quite sufficient for keeping the air in the room sweet and
wholesome; and indeed in rooms in which there is no open Fire-place,
and consequently no current of air from the room setting up the
Chimney, which is the case in Germany, and all the northern parts
of Europe, where rooms are heated by stoves, whose Fire-places
opening without are not supplied with the air necessary for the
combustion of the fuel from the room;--and although in most of
the rooms abroad, which are so heated, the windows and doors are
double, and both are closed in the most exact manner possible,
by slips of paper pasted over the crevices, or by slips of list or
furr; yet when these rooms are tolerably large, and when they are
not very much crowded by company, nor filled with a great many
burning lamps or candles, the air in them is seldom so much
injured as to become oppressive or unwholesome; and those who
inhabit them show by their ruddy countenances, as well as by
every other sign of perfect health, that they suffer no
inconvenience whatever from their closeness.--There is frequently,
it is true, an oppressiveness in the air of a room heated by a
German stove, of which those who are not much accustomed to
living in those rooms seldom fail to complain, and indeed with
much reason; but this oppressiveness does not arise from the air
of the room being injured by the respiration and perspiration of
those who inhabit it;--it arises from a very different cause;--
from a fault in the construction of German stoves in general,
but which may be easily and most completely remedied, as I shall
show more fully in another place. In the mean time, I would just
observe here with regard to these stoves, that as they are often
made of iron, and as this metal is a very good conductor of heat,
some part of the stove in contact with the air of the room
becomes so hot as to calcine or rather to ROAST the dust which
lights upon it; which never can fail to produce a very
disagreeable effect on the air of the room. And even when the
stove is constructed of pantiles or pottery-ware, if any part of
it in contact with the air of the room is suffered to become very
hot, which seldom fails to be the case in German stoves
constructed on the common principles, nearly the same effects
will be found to be produced on the air as when the stove is made
of iron, as I have very frequently had occasion to observe.
Though a room be closed in the most perfect manner possible, yet,
as the quantity of air injured and rendered unfit for further use
by the respiration of two or three persons in a few hours is very
small, compared to the immense volume of air which a room of a
moderate size contains; and as a large quantity of fresh air
always enters the room, and an equal quantity of the warm air of
the room is driven out of it every time the door is opened, there
is much less danger of the air of a room becoming unwholesome for
the want of ventilation than has been generally imagined;
particularly in cold weather, when all the different causes which
conspire to change the air of warmed rooms act with increased
power and effect.
Those who have any doubts respecting the very great change of air
or ventilation which takes place each time the door of a warm room
is opened in cold weather, need only set the door of such a room
wide open for a moment, and hold two lighted candles in the
door-way, one near the top of the door, and the other near the
bottom of it; the violence with which the flame of that above
will be driven outwards, and that below inwards, by the two
strong currents of air which, passing in opposite directions,
rush in and out of the room at the same time, will be convinced
that the change of air which actually takes place must be very
considerable indeed; and these currents will be stronger,
and consequently the change of air greater, in proportion as the
difference is greater between the temperature of the air within
the room and of that without. I have been more particular upon
this subject,--the ventilation of warmed rooms which are
constantly inhabited,--as I know that people in general in this
country have great apprehensions of the bad consequences to
health of living rooms in which there is not a continual influx
of cold air from without. I am as much an advocate for a FREE
CIRCULATION of air as any body, and always sleep in a bed without
curtains on that account; but I am much inclined to think, that
the currents of cold air which never fail to be produced in rooms
heated by Fire-places constructed upon the common principle,--
those partial heats on one side of the body, and the cold blasts
on the other, so often felt in houses in this country, are
infinitely more detrimental to health than the supposed closeness
of the air in a room warmed more equally, and by a smaller fire.
All these advantages, attending the introduction of the
improvements in Fire-places here recommended, are certainly
important, and I do not know that they are counterbalanced by any
one disadvantage whatsoever. The only complaints that I had ever
heard made against them was, that they made the rooms TOO warm;
but the remedy to this evil is so perfectly simple and obvious,
that I should be almost afraid to mention it, less it might be
considered as an insult to the understanding of the persons to
whom such information should be given; for nothing surely can be
conceived more perfectly ridiculous than the embarrassment of a
person on account of the too great heat of his room, when it is
in his power to diminish AT PLEASURE the fire by which it is
warmed; and yet, strange as it may appear, this has sometimes
happened!
Before I proceed to give directions for the construction of
Fire-places, it will be proper to examine more carefully the
Fire-places now in common use;--to point out their faults;--
and to establish the principles upon which Fire-places ought to
be constructed.
The great fault of all the open Fire-places, or Chimnies, for
burning wood or coals in an open fire, now in common use, is,
that they are much too large; or rather it is THE THROAT OF THE
CHIMNEY or the lower part of its open canal, in the neighbourhood
of the mantle, and immediately over the fire, which is too large.
This opening has hitherto been left larger than otherwise it
probably would have been made, in order to give a passage to the
Chimney-sweeper; but I shall show hereafter how a passage for the
Chimney-sweeper may be contrived without leaving the throat of
the Chimney of such enormous dimensions as to swallow up and
devour all the warm air of the room, instead of merely giving a
passage to the smoke and heated vapour which rise from the fire,
for which last purpose alone it ought to be destined.
Were it my intention to treat my subject in a formal scientific
manner, it would be doubtless be proper, and even necessary, to
begin by explaining in the fullest manner, and upon the
principles founded on the laws of nature, relative to the motions
of elastic fluids, as far as they have been discovered and
demonstrated, the causes of the ascent of smoke, and also to
explain and illustrate upon the same principles, and even to
measure, or estimate by calculations, the precise effects of all
those mechanical aids which may be proposed for assisting it in
its ascent, or rather for removing those obstacles which hinder
its motion upwards;--but as it is my wish rather to write an
useful practical treatise, than a learned dissertation, being
more desirous to contribute in diffusing useful knowledge, by
which the comforts and enjoyments of mankind may be increased,
than to acquire the reputation of a philosopher among learned
men, I shall endeavour to write in such a manner as to be easily
understood BY THOSE WHO ARE MOST LIKELY TO PROFIT BY THE
INFORMATION I HAVE TO COMMUNICATE, and consequently most likely
to assist in bringing into general use the improvements I
recommend. This being premised, I shall proceed, without any
further preface or introduction, to the investigation of the
subject I have undertaken to treat.
As the immoderate size of the throats of Chimnies is the great
fault of their construction, it is this fault which ought always
to be first attended to in every attempt which is made to improve
them; for however perfect the construction of a Fire-place may be
in other respects, if the opening left for the passage of the smoke
is larger than is necessary for that purpose, nothing can prevent
the warm air of the room from escaping through it; and whenever
this happens, there is not only an unnecessary loss of heat,
but the warm air which leaves the room to go up the Chimney being
replaced by cold air from without, the draughts of cold air,
so often mentioned, cannot fail to be produced in the room, to the
great annoyance of those who inhabit it. But although both these
evils may be effectually remedied by reducing the throat of the
Chimney to a proper size, yet in doing this several precautions
will be necessary. And first of all, the throat of the Chimney
should be in its proper place; that is to say, in that place in
which it ought to be, in order that the ascent of the smoke may
be most facilitated; for every means which can be employed for
facilitating the ascent of the smoke in the Chimney must naturally
tend to prevent the Chimney from smoking: now as the smoke and
hot vapour which rise from a fire naturally tend UPWARDS, the
proper place for the throat of the Chimney is evidently
perpendicularly OVER THE FIRE.
But there is another circumstance to be attended to in
determining the proper place for the throat of a Chimney,
and that is, to ascertain its distance from the fire, or HOW FAR
above the burning fuel it ought to be placed. In determining
this point, there are many things to be considered, and several
advantages and disadvantages to be weighed and balanced.
As the smoke and vapour which ascend from burning fuel rise in
consequence of their being rarefied by heat, and made lighter
than the air of the surrounding atmosphere; and as the degree of
their rarefaction, and consequently their tendency to rise, is in
proportion to the intensity of their heat; and further, as they
are hotter near the fire than at a greater distance from it,
it is clear that the nearer the throat of a Chimney is to the fire,
the stronger will be, what is commonly called, its DRAUGHT,
and the less danger there will be of its smoking. But on the
other hand, when the draught of a Chimney is very strong, and
particularly when this strong draught is occasioned by the throat
of the Chimney being very near the fire, it may so happen that
the draught of air into the fire may become so strong, as to
cause the fuel to be consumed too rapidly. There are likewise
several other inconveniences which would attend the placing of
the throat of a Chimney VERY NEAR the burning fuel.
In introducing the improvements proposed, in Chimnies already built,
there can be no question in regard to the height of the throat of
the Chimney, for its place will be determined by the height of
the mantle. It can hardly be made lower than the mantle; and it
ought always to be brought down as nearly upon the level with the
bottom of it as possible. If the Chimney is apt to smoke,
it will sometimes be necessary either to lower the mantle or to
diminish the height of the opening of the Fire-place, by throwing
over a flat arch, or putting in a straight piece of stone from
one side of it to the other, or, which will be still more simple
and easy in practice, building a wall of bricks, supported by a
flat bar of iron, immediately under the mantle.
Nothing is so effectual to prevent Chimnies from smoking as
diminishing the opening of the Fire-place in the manner here
described, and lowering and diminishing the throat of the Chimney;
and I have always found, except in the single instance already
mentioned, that a perfect cure may be effected by THESE MEANS
ALONE, even in the most desperate cases. It is true, that when
the construction of the Chimney is very bad indeed, or its
situation very unfavourable to the ascent of the smoke, and
especially when both these disadvantages exist at the same time,
it may sometimes be necessary to diminish the opening of the
Fire-place, and particularly to lower it, and also to lower the
throat of the Chimney, more than might be wished: but still I
think this can produce no inconveniences to be compared with that
greatest of all plagues, a smoking Chimney.
The position of the throat of a Chimney being determined, the
next points to be ascertained are its size and form, and the
manner in which it ought to be connected with the Fire-place
below, and with the open canal of the Chimney above.
But as these investigations are intimately connected with those
which relate to the form proper to be given to the Fire-place
itself, we must consider them all together.
That these inquiries may be pursued with due method, and that the
conclusions drawn from them may be clear and satisfactory,
it will be necessary to consider, first, what the objects are
which ought principally to be had in view in the construction of
a Fire-place; and secondly, to see how these objects can best be
attained.
Now the design of a Chimney Fire being simply to warm a room,
it is necessary, first of all, to contrive matters so that the
room shall be actually warmed; secondly, that it be warmed with
the smallest expence of fuel possible; and, thirdly, that in
warming it, the air of the room be preserved perfectly pure,
and fit for respiration, and free from smoke and all disagreeable
smells.
In order to take measures with certainty for warming a room by
means of an open Chimney Fire, it will be necessary to consider
HOW, or in WHAT MANNER, such a Fire communicates heat to a room.
This question may perhaps, at the first view of it, appear to be
superfluous and trifling, but a more careful examination of the
matter will show it to be highly deserving of the most attentive
investigation.
To determine in what manner a room is heated by an open Chimney
Fire, it will be necessary first of all to find out, UNDER WHAT
FORM the heat generated in the combustion of the fuel exists,
and then to see how it is communicated to those bodies which are
heated by it.
In regard to the first of these subjects of inquiry, it is quite
certain that the heat which is generated in the combustion of the
fuel exists under TWO perfectly distinct and very different forms.
One part of it is COMBINED with the smoke, vapour, and heated air
which rise from the burning fuel, and goes off with them into the
upper regions of the atmosphere; while the other part, which
appears to be UNCOMBINED, or, as some ingenious philosophers have
supposed, combined only with light, is sent off from the fire in
rays in all possible directions.
With respect to the second subject of inquiry; namely, how this
heat, existing under these two different forms, is communicated
to other bodies; it is highly probable that the combined heat can
only be communicated to other bodies by ACTUAL CONTACT with the
body with which it is combined; and with regard to the rays which
are sent off by burning fuel, it is certain that THEY communicate
or generate heat only WHEN and WHERE they are stopped or
absorbed. In passing through air, which is transparent, they
certainly do not communicate any heat to it; and it seems highly
probable that they do not communicate heat to solid bodies by
which they are reflected.
In these respects they seem to bear a great resemblance to the
solar rays. But in order not to distract the attention of my
reader, or carry him too far away from the subject more
immediately under consideration, I must not enter too deeply into
these inquiries respecting the nature and properties of what has
been called RADIANT HEAT. It is certainly a most curious subject
of philosophical investigation, but more time would be required
to do it justice than we now have to spare. We must therefore
content ourselves with such a partial examination of it as will
be sufficient for our present purpose.
A question which naturally presents itself here is.
What proportion does the radiant heat bear to the combined
heat?--Though that point has not yet been determined with any
considerable degree of precision, it is, however, quite certain,
that the quantity of heat which goes off combined with the smoke,
vapour, and heated air is much more considerable, perhaps three
of four times greater at least, than that which is sent off from
the fire in rays.--And yet, small as the quantity is of this
radiant heat, it is the only part of the heat generated in the
combustion of fuel burnt in an open Fire-place which is ever
employed, or which can ever be employed, in heating a room.
The whole of the combined heat escapes by the Chimney, and is
totally lost; and, indeed, no part of it could ever be brought
into a room from an open Fire-place, without bringing along with
it the smoke with which it is combined; which, of course, would
render it impossible for the room to be inhabited. There is,
however, one method by which combining heat, and even that which
arises from an open Fire-place, may be made to assist in warming
a room; and that is by making it pass through something analogous
to a German stove, placed in the Chimney above the fire.--But of
this contrivance I shall take occasion to treat more fully
hereafter; in the mean time I shall continue to investigate the
properties of open Chimney Fire-places, constructed upon the most
simple principles, such as are now in common use; and shall
endeavour to point out and explain all those improvements of
which THEY appear to me to be capable. When fuel is burnt in
Fire-places upon this simple construction, where the smoke
escapes immediately by the open canal of the Chimney, it is quite
evident that all the combined heat must of necessity be lost; and
as it is the radiant heat alone which can be employed in heating
a room, it becomes an object of much importance to determine how
the greatest quantity of it may be generated in the combustion of
the fuel, and how the greatest proportion possible of that
generated may be brought into the room.
Now the quantity of radiant heat generated in the combustion of a
given quantity of any kind of fuel depends very much upon the
management of the fire, or upon the manner in which the fuel is
consumed. When the fire burns bright, much radiant heat will be
sent off from it; but when it is SMOTHERED UP, very little will
be generated; and indeed very little combined heat, that can be
employed to any useful purpose: most of the heat produced will be
immediately EXPENDED in giving elasticity to a thick dense vapour
or smoke which will be seen rising from the fire; -- and the
combustion being very incomplete, a great part of the inflammable
matter of the fuel being merely rarefied and driven up the
Chimney without being inflamed, the fuel will be wasted to little
purpose. And hence it appears of how much importance it is,
whether it be considered with a view to economy, or to
cleanliness, comfort, and elegance, to pay due attention to the
management of a Chimney Fire.
Nothing can be more perfectly void of common sense, and wasteful
and slovenly at the same time, than the manner in which Chimney
Fires, and particularly where coals are burned, are commonly
managed by servants. They throw on a load of coals at once,
through which the flame is hours in making its way; and
frequently it is not without much trouble that the fire is
prevented from going quite out. During this time no heat is
communicated to the room; and what is still worse, the throat of
the Chimney being occupied merely by a heavy dense vapour,
not possessed of any considerable degree of heat, and consequently
not having much elasticity, the warm air of the room finds less
difficulty in forcing its way up the Chimney and escaping,
than when the fire burns bright;--and it happens not unfrequently,
especially in Chimneys and Fire-places ill constructed, that this
current of warm air from the room which presses into the Chimney,
crossing upon the current of heavy smoke which rises slowly from
the fire, obstructs it in its ascent, and beats it back into the
room; hence it is that Chimnies so often smoke when too large a
quantity of fresh coals is put upon the fire. So many coals
should never be put on the fire at once as to prevent the free
passage of the flame between them. In short, a fire should never
be smothered; and when proper attention is paid to the quantity
of coals put on, there will be very little use for the poker;
and this circumstance will contribute very much to cleanliness,
and to the preservation of furniture.
Those who have feeling enough to be made miserable by any thing
careless, slovenly, and wasteful which happens under their
eyes,--who know what comfort is, and consequence are worthy of
the enjoyments of a CLEAN HEARTH and a CHEERFUL FIRE, should
really either take the trouble themselves to manage their fires,
(which, indeed, would rather be an amusement to them than a
trouble,) or they should instruct their servants to manage them
better.
But to return to the subject more immediately under consideration.
As we have seen what is necessary to the production or generation
of radiant heat, it remains to determine how the greatest
proportion of that generated and sent off from the fire in all
directions may be made to enter the room, and assist in warming
it. How as the rays which are thrown off from burning fuel have
this property in common with light, that they generate heat only
WHEN and WHERE they are stopped or absorbed, and also in being
capable of being reflected WITHOUT GENERATING at the surfaces of
various bodies, the knowledge of these properties will enable us
to take measures, with the utmost certainty, for producing the
effect required,--that is to say, for bringing as much radiant
heat as possible into the room.
This must be done, first, by causing as many as possible of the
rays, as they are sent off from the fire in straight lines,
to come DIRECTLY into the room; which can only be effected by
bringing the fire as far forward as possible, and leaving the
opening of the Fire-place as wide and as high as can be done
without inconveniences; and secondly, by making the sides and
back of the Fire-place of such form, and constructing them of
such materials, as to cause the direct rays from the fire,
which strike against them, to be sent into the room BY REFLECTION
in the greatest abundance.
Now it will be found, upon examination, that the best form for
the vertical sides of a Fire-place, or the COVINGS, (as they are
called,) is that of an upright plane, making an angle with the
plane of the back of the Fire-place, of about 135 degrees.--
According to the present construction of Chimnies this angle is
90 degrees, or forms a right angle; but as in this case the two
sides or covings of the Fire-place (AC, BD, Fig. 1.) are
parallel to each other, it is evident that they are very ill
contrived for throwing into the room by reflection the rays from
the fire which fall on them.
To have a clear and perfect idea of the alterations I propose in
the forms of Fire-places, the reader need only observe, that,
whereas the backs of Fire-places, as they are now commonly
constructed, are as wide as the opening of the Fire-place in
front, and the sides of it are of course perpendicular to it, and
parallel to each other,--in the Fire-places I recommend, the back
(i k, Fig. 3) is only about one-third of the width of the opening
of the Fire-place in front (a,b), and consequently that the two
sides of covings of the Fire-place (a i and b k), instead of
being perpendicular to the back, are inclined to it at an angle
of about 135 degrees; and in consequence of this position,
instead of being parallel to each other, each of them presents an
oblique front towards the opening of the Chimney, by means of
which the rays which they reflect are thrown into the room.
A bare inspection of the annexed drawings (Fig. 1. and Fig. 3.)
will render this matter perfectly clear and intelligible.
In regard to the materials which it will be most advantageous to
employ in the construction of Fire-places, so much light has,
I flatter myself, already been thrown on the subject we are
investigating, and the principles adopted have been established
on such clear and obvious facts, that no great difficulty will
attend the determination of that point.--As the object in view is
to bring radiant heat into the room, it is clear that that
material is best for the construction of a Fire-place which
reflects the most, or which ABSORBS THE LEAST of it; for that
heat which is ABSORBED cannot be REFLECTED--Now as bodies which
absorb radiant heat are necessarily heated in consequence of that
absorption, to discover which of the various materials that can
be employed for constructing Fire-places are best adapted for
that purpose, we have only to find out by an experiment, very
easy to be made, what bodies acquire LEAST HEAT when exposed to
the direct rays of a clear fire;--for those which are least
heated, evidently absorb the least, and consequently reflect the
most radiant heat. And hence it appears that iron, and, in
general, metals of all kinds, which are well known to GROW VERY
HOT when exposed to the rays projected by burning fuel, are to be
reckoned among the VERY WORST materials that it is possible to
employ in the construction of Fire-places.
The best materials I have hitherto been able to discover are
fire-stone, and common bricks and mortar. Both these materials
are, fortunately, very cheap; and as to their comparative merits,
I hardly know to which of them the preference ought to be given.
When bricks are used they should be covered with a thin coating
of plaster, which, when it is become perfectly dry, should be
white-washed. The fire-stone should likewise be white washed,
when that is used; and every part of the Fire-place, which is not
exposed to being soiled and made black by the smoke, should be
kept as white and clean as possible. As WHITE reflects more
heat, as well as more light than any other colour, it ought
always to be preferred for the inside of a Chimney Fire-place,
and BLACK, which reflects neither light nor heat should be most
avoided.
I am well aware how much the opinion I have have ventured to
give, respecting the unfitness of iron and other metals to be
employed in the construction of open Fire-places, differs from
the opinion generally received upon that subject;--and I even
know that the very reason which, according to my ideas of the
matter, renders them totally unfit for the purpose, is commonly
assigned for making use of them, namely, that they soon grow very
hot. But I would beg leave to ask what advantage is derived from
heating them?
I have shown the disadvantage of it, namely, that the quantity of
radiant heat thrown into the room is diminished;--and it is easy
to show that almost the whole of that absorbed by the metal is
ultimately carried up the Chimney by the air, which, coming into
contact with this hot metal, is heated and rarefied by it,
and forcing its way upwards, goes off with the smoke; and as no
current of air ever sets from any part of the opening of a
Fire-place into the room, it is impossible to conceive how the
heat existing in the metal composing any part of the apparatus of
the Fire-place, and situated within its cavity, can come, or be
brought into the room.
This difficulty may be in part removed, by supposing, what
indeed seems to be true in a certain degree, that the heated
metal sends off rays, the heat it acquires from the fire, even
when it is not heated red hot; but still, as it never can be
admitted that the heat, absorbed by the metal and afterwards
thrown off by it in rays, is INCREASED by this operation, nothing
can be gained by it; and as much must necessary be lost in
consequence of the great quantity of heat communicated by the hot
metal to the air in contact with it, which, as has already been
shown, always makes its way up the Chimney, and flies off into
the atmosphere, the loss of heat attending the use of it is too
evident to require being farther insisted on.
There is, however, in Chimney Fire-places destined for burning
coals, one essential part, the grate, which cannot well be made
of any thing else but iron; but there is no necessity whatever
for that immense quantity of iron which surrounds grates as they
are now commonly constructed and fitted up, and which not only
renders them very expensive, but injures very essentially the
Fire-place. If it should be necessary to diminish the opening of
a large Chimney in order to prevent its smoking, it is much more
simple, economical, and better in all respects, to do this with
marble, fire-stone, or even with bricks and mortar, than to make
use of iron, which, as has already been shown, is the very worst
material that can possibly be employed for that purpose; and as
to registers, they not only are quite unnecessary, where the
throat of a Chimney is properly constructed, and of proper
dimensions, but in that case would do much harm. If they act at
all, it must be by opposing their flat surfaces to the current of
rising smoke in a manner which cannot fail to embarrass and
impede its motion. But we have shown that the passage of the
smoke through the throat of a Chimney ought to be facilitated as
much as possible, in order that it may be enabled to pass by a
small aperture.
Register-stoves have often been found to be of use, but it is
because the great fault of all Fire-places constructed upon the
common principles being the enormous dimensions of the throat of
the Chimney, this fault has been in some measure corrected by
them; but I will venture to affirm, that there never was a
Fire-place so corrected that would not have been much more
improved, and with infinitely less expence, by the alterations
here recommended, and which will be more particularly explained
in the next Chapter.
CHAPTER. II.
Practical directions designed for the use of workmen, showing
how they are to proceed in making the alterations necessary to
improve chimney fire-places, and effectually to cure smoking
chimnies.
All Chimney Fire-places, without exception, whether they are
designed for burning wood or coals, and even those which do not
smoke, as well as those which do, may be greatly improved by
making the alterations in them here recommended; for it is by no
means MERELY to prevent Chimnies from smoking that these
improvements are recommended, but it is also to make them better
in all other respects as Fire-places; and when the alterations
proposed are properly executed, which may be very easily be done
with the assistance of the following plain and simple
directions, the Chimnies will never fail to answer, I will
venture to say, even beyond expectation. The room will be heated
much more equally and more pleasantly with LESS THAN HALF THE
FUEL used before, the fire will be more cheerful and more
agreeable; and the general appearance of the Fire-place more neat
and elegant, and the Chimney WILL NEVER SMOKE.
The advantages which are derived from mechanical inventions and
contrivances are, I know, frequently accompanied by disadvantages
which it is not always possible to avoid; but in the case in
question, I can say with truth, that I know of no disadvantage
whatever that attends the Fire-places constructed upon the
principles here recommended. --But to proceed in giving
directions for the construction of these Fire-places.
That what I have to offer on this subject may be the more easily
understood, it will be proper to begin by explaining the precise
meaning of all those technical words and expressions which I may
find it necessary or convenient to use.
By the THROAT of a Chimney, I mean the lower extremity of its
canal, where it unites with the upper part of its open Fire-place.
--This throat is commonly found about a foot above the level of
the lower part of the mantle, and it is sometimes contracted to a
smaller size than the rest of the canal of the Chimney,
and sometimes not.
Fig. 5. shows the section of a Chimney on the common
construction, in which d e is the throat.
Fig. 6. shows the section of the same Chimney altered and
improved, in which d i is the reduced throat.
The BREAST of a Chimney, is that part of it which is immediately
behind the mantle.--It is the wall which forms the entrance from
below into the throat of the Chimney in front, or towards the
room.--It is opposite to the upper extremity of the back of the
open Fire-place, and parallel to it; in short it may said to be
the back part of the mantle itself.--In the figures 5 and 6,
it is marked by the letter d. The WIDTH of the throat of Chimney
(d e fig. 5, and d i fig. 6,) is taken from the breast of the
Chimney to the back, and its LENGTH is taken at right angles to
its width, or in a line parallel to the mantle (a fig. 5. and 6.).
Before I proceed to give particular directions respecting the
exact forms and dimensions of the different parts of a Fire-place,
it may be useful to make such general an practical observations
upon the subject as can be clearly understood without the
assistance of drawings; for the more complete the knowledge of
any subject is which can be acquired without drawings, the more
easy will it be to understand the drawings when it becomes
necessary to have recourse to them.
The bringing forward of the Fire into the room, or rather
bringing it nearer to the front of the opening of the
Fire-place;--and the diminishing of the throat of the Chimney,
being two objects principally had in view in the alterations in
Fire-places here recommended, it is evident that both these may
be attained merely by bringing forward the back of the Chimney.
--The only question therefore is, how far it should be brought
forward?--The answer is short, and easy to be understood;--bring
it forward as far as possible, without diminishing too much the
passage which must be left for the smoke. Now as this passage,
which, in its narrowest part, I have called the THROAT OF THE
CHIMNEY, ought, for reasons which are fully explained in the
foregoing Chapter, to be immediately, or perpendicularly over the
Fire, it is evident that the back of the Chimney must always be
built perfectly upright.--To determine therefore the place for
the new back, or how far precisely it ought to be brought
forward, nothing more is necessary than to ascertain how wide
the throat of the Chimney ought to be left, or what space must be
left, between the top of the breast of the Chimney, where the
upright canal of the Chimney begins, and the new back of the
Fire-place carried up perpendicularly to that height.
In the course of my numerous experiments upon Chimnies, I have
taken much pains to determine the width proper to be given to
this passage, and I have found, that, when the back of the
Fire-place is of a proper width, the best width for the throat of
a Chimney, when the Chimney and the Fire-place are at the usual
form and size, is FOUR INCHES.--Three inches might sometimes
answer, especially where the Fire-place is very small, and the
Chimney good, and well situated: but as it is always of much
importance to prevent those accidental puffs of smoke which are
sometimes thrown into rooms by the carelessness of servants in
putting on suddenly too many coals at once upon the fire, and as
I found these accidents sometimes happened when the throats of
Chimneys were made very narrow, I found that, upon the whole, all
circumstances being well considered, and advantages and
disadvantages compared and balanced, FOUR INCHES is the best
width that can be given to the throat of a chimney; and this,
whether the Fire-place be destined to burn wood, coals, turf,
or any other fuel commonly used for heating rooms by an open fire.
In Fire-places destined for heating very large halls, and where
very great fires are kept up, the throat of the Chimney may,
if it should be thought necessary, be made four inches and an half,
or five inches wide;--but I have frequently made Fire-places for
halls which have answered perfectly well where the throats of
the Chimnies have not been wider than four inches.
It may perhaps appear extraordinary, upon the first view of the
matter, that Fire-places of such different sizes should all
require the throat of the Chimney to be of the same width; but
when it is considered that the CAPACITY of the throat of a
Chimney does not depend on its width alone, but on its width and
LENGTH taken together; and that in large Fire-places, the width
of the back, and consequently the length of the throat of the
Chimney, is greater than in those which are smaller, this
difficulty vanishes.
And this leads us to consider another important point respecting
open Fire-places, and that is, the width which it will, in each
case, be proper to give to the back.--In Fire-places as they are
now commonly constructed, the back is of equal width with the
opening of the Fire-place in front;--but this construction is
faulty on two accounts.--First, in a Fire-place, so constructed,
the sides of the Fire-place, or COVINGS, as they are called, are
parallel to each other, and consequently ill-contrived to throw
out into the room the heat they receive from the fire in the form
of rays;--and secondly, the large open corners which are formed
by making the back as wide as the opening of the Fire-place in
front occasion eddies of wind, which frequently disturb the fire,
and embarrass the smoke in its ascent in such a manner as often
to bring it into the room.--Both these defects may be entirely
remedied by diminishing the width of the back of the Fire-place.
--The width which, in most cases, it will be best to give it,
is ONE THIRD of the width of the opening of the Fire-place in
front.--But it is not absolutely necessary to conform rigorously
to this decision, nor will it always be possible.--It will
frequently happen that the back of a Chimney must be made wider
than, according to the rule here given, it ought to be.--This
may be, either to accommodate the Fire-place to a stove, which
being already on hand, must, to avoid the expense of purchasing a
new one, be employed; or for other reasons;--and any small
deviation from the general rule will be attended with no
considerable inconvenience.--It will always be best, however,
to conform to it as far as circumstances will allow.
Where a Chimney is designed for warming a room of a middling size,
and where the thickness of the wall of the Chimney in front,
measured from the front of the mantle to the breast of the
Chimney, is nine inches, I should set off four inches more for
the width of the throat of the Chimney, which, supposing the back
of the Chimney to be built upright, as it always ought to be,
will give thirteen inches for the depth of the Fire-place,
measured upon the hearth, from the opening of the Fire-place in
front, to the back.--In this case thirteen inches would be a good
size for the width of the back; and three times thirteen inches,
or thirty-nine inches, for the width of the opening of the
Fire-place in front; and the angle made by the back of the
Fire-place and the sides of it, or covings, would be just 135
degrees, which is the best position they can have for throwing
heat into the room.
But I will suppose that in altering such a Chimney it is found
necessary, in order to accommodate the Fire-place to a grate or
stove already on hand, to make the Fire-place sixteen inches
wide. -- In that case, I should merely increase the width of the
back, to the dimensions required, without altering the depth of
the Chimney, or increasing the width of the opening of the
Chimney in front. --The covings, it is true, would be somewhat
reduced in their width, by this alteration; and their position
with respect to the plane of the back of the Chimney would be a
little changed; but these alterations would produce no bad
effects of any considerable consequence, and would be much less
likely to injure the Fire-place, than an attempt to bring the
proportions of its parts nearer to the standard, by increasing
the depth of the Chimney, and the width of its opening in
front;--or than an attempt to preserve that particular obliquity
of the covings which is recommended as the best, (135 degrees,)
by increasing the width of the opening of the Fire-place, without
increasing its depth.
In order to illustrate this subject more fully, we will suppose
one case more.--We will suppose that in the Chimney which is to
be altered, the width of the Fire-place in front is either wider
or narrower than it ought to be, in order that the different
parts of the Fire-place, after it is altered, may be of the
proper dimensions. In this case, I should determine the depth of
the Fire-place, and the width of the back of it, without any
regard to the width of the opening of the Fire-place in front;
and when this is done, if the opening of Fire-place should be
only two or three inches too wide, that is to say, only two or
three inches wider than is necessary in order that the covings
may be brought into their proper position with respect to the
back, I should not alter the width of this opening, but should
accommodate the covings to this width, by increasing their
breadth, and increasing the angle they make with the back of the
Fire-place; but if the opening of the Fire-place should be more
than three inches too wide; --I should reduce it to the proper
width by slips of stone, or by bricks and mortar.
When the width of the opening of the Fire-place, in front, is
very great, compared with the depth of the Fire-place, and with
the width of the back, the covings in that case being very wide,
and consequently very oblique, and the Fire-place very shallow,
any sudden motion of the air in front of the Fire-place, (that
motion, for instance, which would be occasioned by the clothes
of a woman passing hastily before the fire, and very near it,)
would be apt to cause eddies in the air, WITHIN THE OPENING OF
THE FIRE-PLACE, by which puffs of smoke might easily be brought
into the room. Should the opening of the Chimney be too narrow,
which however will very seldom be found to be the case, it will,
in general, be advisable to let it remain as it is, and to
accommodate the covings to it, rather to attempt to increase its
width, which would be attended with a good deal of trouble, and
probably a considerable expence.
From all that has been said it is evident, that the points of the
greatest importance, and which ought most particularly to be
attended to, in altering Fire-places upon the principles here
recommended, are, the bringing forward the back to its proper
place, and making it of a proper width.--But it is time that I
should mention another matter upon which it is probable that my
reader is already impatient to receive information.--Provision
must be made for the passage of the Chimney-sweeper up the
Chimney.--This may easily be done in the following manner:--
In building up the new back of the Fire-place; when this wall,
(which need never be more than the width of a single brick in
thickness,) is brought up so high that there remains no more than
about ten or eleven inches between what is then the top of it,
and the inside of the mantle, or lower extremity of the breast of
the Chimney, an opening, or door-way, eleven or twelve inches
wide, must be begun in the middle of the back, and continued
quite to the top of it, which, according to the height to which
it will commonly be necessary to carry up the back, will make the
opening about twelve or fourteen inches high; which will be quite
sufficient to allow the Chimney-sweeper to pass. When the
Fire-place is finished, this door-way is to be closed by a few
bricks, by a tile, or a fit piece of stone, placed in it, dry,
or without mortar, and confined in its place by means of a rabbet
made for that purpose in the brick-work.--As often as the Chimney
is swept, the Chimney-sweeper takes down this temporary wall,
which is very easily done, and when he has finished his work, he
puts it again into its place.--The annexed drawing (No. 6.) will
give a clear idea of this contrivance; and the experience I have
had of it has proved that it answers perfectly well the purpose
for which it is designed.
I observed above, that the new back, which it will always be
found necessary to build in order to bring the fire sufficiently
forward, in altering a Chimney constructed on the common
principles, need never be thicker than the width of a common
brick.--I may say the same of the thickness necessary to be given
to the new sides, or covings, of the Chimney; or if the new back
and covings are constructed of stone, one inch and three
quarters, or two inches in thickness will be sufficient.--Care
should be taken in building up these new walls to unite the back
to the covings in a solid manner.
Whether the new back and covings are constructed of stone,
or built of bricks, the space between them, and the old back and
covings of the Chimney ought to be filled up, to give greater
solidity to the structure.--This may be done with loose rubbish,
or pieces of broken bricks, or stones provided the work be
strengthened by a few layers or courses of bricks laid in mortar;
but it will be indispensably necessary to finish the work, where
these new walls end, that is to say, at the top of the throat of
the Chimney, where it ends abruptly in the open canal of the
Chimney by a horizontal course of bricks well secured with mortar.
--This course of bricks will be upon a level with the top of the
door-way left for the Chimney-sweeper.
From these descriptions it is clear that where the throat of the
Chimney has an end, that is to say, where it enters into the
lower part of the open canal of the Chimney, THERE the three
walls which form the two covings and the back of the Fire-place
all end abruptly.--It is of much importance that they should end
in this manner; for were they to be sloped outward and raised in
such a manner as to swell out the upper extremity of the throat
of the Chimney in the form of a trumpet, and increase it by
degrees to the size of the canal of the Chimney, this manner of
uniting the lower extremity of the canal of the Chimney with the
throat would tend to assist the winds which may attempt to blow
down the Chimney, in forcing their way through the throat, and
throwing the smoke backward into the room; but when the throat of
the Chimney ends abruptly, and the ends of the new walls form a
flat horizontal surface, it will be much more difficult for any
wind from above, to find, and force its way through the narrow
passage of the throat of the Chimney.
As the two walls which form the new covings of the Chimney are
not parallel to each other; but inclined, presenting an oblique
surface towards the front of the Chimney, and as they are built
perfectly upright and quite flat, from the hearth to the top of
the throat, where they end, it is evident that an horizontal
section of the throat will not be an oblong square; but its
deviation from that form is a matter of no consequence; and no
attempts should ever be made, by twisting the covings above,
where they approach the breast of the Chimney, to bring it to
that form.--All twists, bends, prominences, excavations,
and other irregularities of form, in the covings of a Chimney,
never fail to produce eddies in the current of air which is
continually passing into, and through an open Fire-place in which
a fire is burning;--and all such eddies disturb, either the fire,
or the ascending currents of smoke, or both; and not unfrequently
cause the smoke to be thrown back into the room.--Hence it appears,
that the covings of Chimneys should never be made circular, or in
the form of any other curve; but always quite flat.
For the same reason, that is to say, to prevent eddies,
the breast of the Chimney, which forms that side of the throat
that is in front, or nearest to the room, should be nearly
cleaned off, and its surface made quite regular and smooth.
This may easily be done by covering it with a coat of plaster,
which may be made thicker or thinner in different parts as may be
necessary in order to bring the breast of the Chimney to be of
the proper form.
With regard to the form of the breast of a Chimney, this is a
matter of very great importance, and which ought always to be
particularly attended to.--The worst form it can have is that of
a vertical plane, or upright flat;--and next to this the worst
form is an inclined plane.--Both these forms cause the current
of warm air from the room, which will, in spite of every
precaution, sometimes find its way into the Chimney, to cross
upon the current of smoke, which rises from the fire, in a manner
most likely to embarrass it in its ascent, and drive it back.
--The inclined plane which is formed by a flat register placed in
the throat of a Chimney produces the same effects; and this is
one reason, among many others, which have induced me to
disapprove of register stoves.
The current of air, which, passing under the mantle, gets into
the Chimney, should be made GRADUALLY TO BEND ITS COURSE UPWARDS,
by which means it will be QUIETLY with the ascending current of
smoke, and will be less likely to check it, or force it back into
the room.--Now this may be effected with the greatest ease and
certainty, merely by ROUNDING OFF the breast of the Chimney or
back part of the mantle, instead of leaving it flat, or full of
holes and corners; and this of course ought always to be done.
I have hitherto given no precise directions in regard to the
height to which the new back and covings ought to be carried:--
This will depend not only on the height of the mantle, but also,
and more especially, on the height of the breast of the Chimney,
or of that part of the Chimney where the breast ends and the
upright canal begins.--The back and covings must rise a few
inches, five or six for instance, higher than this part,
otherwise the throat of the Chimney will not be properly
formed:--but I know of no advantages that would be gained by
carrying them up still higher.
I mentioned above, that the space between the walls which form
the new back and covings, and the old back and sides of the
Fire-place, should be filled up:--but this must not be understood
to apply to the space between the wall of dry bricks, or the tile
which closes the passage for the Chimney-sweeper, and the old
back of the Chimney; for that space must be left void, otherwise,
though this tile (which at most will not be more than two inches
in thickness,) were taken away, there would not be any room
sufficient for him to pass.
In forming this door-way, the best method of proceeding is to
place the tile or flat piece of stone destined for closing it, in
its proper place; and to build round it, or rather by the sides
of it; taking care not to bring any mortar near it, in order that
it may be easily removed when the door-way is finished.--With
regard to the rabbet which should be made in the door-way to
receive it and fix it more firmly in its place, this may either
be formed at the same time when the door-way is built, or it may
be made after it is finished, by attaching to its bottom and
sides, with strong mortar, pieces of thin roof tiles. Such as
are about half an inch in thickness will be best for this use;
if they are thicker, they will diminish too much the opening of
the door-way, and will likewise be more liable to be torn away by
the Chimney-sweeper in passing up and down the Chimney.
It will hardly be necessary for me to add, that the tile, or flat
stone, or wall of dry bricks, which is used for closing up the
door-way, must be of sufficient height to reach quite up to a
level with the top of the walls which form the new back and
covings of the Chimnies.
I ought, perhaps, to apologize for having been so very particular
in these description and explanations, but it must be remembered
that this chapter is written principally for the information of
those who, having had few opportunities of employing their
attention in abstruse philosophical researches, are not
sufficiently practised in these intricate investigations, to
seize, with facility, new ideas;--and consequently, that I have
frequently been obliged TO LABOUR to make myself understood.
I have only to express my wishes that my reader may not be more
FATIGUED with this labour than I have been;--for we shall them
most certainly be satisfied with each other.--But to return once
more to the charge.
There is one important circumstance respecting Chimney Fire-places,
destined for burning coals, which still remains to be farther
examined;--and that is the Grate.
Although there are few grates that may not be used in Chimneys
constructed or altered upon the principles here recommended,
yet they are not, by any means, all equally well adapted for that
purpose.--Those whose construction is the most simple, and which
of course are the cheapest, are beyond comparison the best,
ON ALL ACCOUNTS.--Nothing being wanted in these Chimnies but merely
a grate for containing the coals, and in which they will burn
with a clear fire;--and all additional apparatus being, not only
useless, but very pernicious, all complicated and expensive
grates should be laid aside, and such as more simple substituted
in the room of them.--And in the choice of a grate, as in every
thing else, BEAUTY and ELEGANCE may easily be united with the
MOST PERFECT SIMPLICITY.--Indeed they are incompatible with every
thing else.
In placing the grate, the thing principally to be attended to is,
to make the back of it coincide with the back of the Fire-place;--
but as many of the grates now in common use will be found to be
too large, when the Fire-places are altered and improved, it
will be necessary to diminish their capacities by filling them up
at the back and the sides with pieces of fire-stone. When this
is done, it is the front of the flat piece of fire-stone which is
made to form a new back to the grate, which must be made to
coincide with, and make part of the back, of the Fire-place.--
But in diminishing the capacities of grates with pieces of
fire-stone, care must be taken not to make them TOO NARROW.
The proper width for grates destined for rooms of a middling size
will be from six to eight inches, and their length may be
diminished more or less, according as the room is heated with
more or less difficulty, or as the weather is more or less severe.
--But where the width of a grate is not more than five inches,
it will be very difficult to prevent the fire from going out.
It goes out for the same reason that a live coal from the grate
that falls upon the hearth soon ceases to be red hot;--it is
cooled by the surrounding cold air of the atmosphere.--
The knowledge of the cause which produces this effect is important,
as it indicates the means which may be used for preventing it.
--But of this subject I shall treat more fully hereafter.
It frequently happens that the iron backs of grates are not
vertical, or upright, but inclined backwards.--When these grates
are so much too wide as to render it necessary to fill them up
behind with fire-stone, the inclination of the back will be of
little consequence; for by making the piece of stone with which
the width of the grate is to be diminished in the form of a
wedge, or thicker above than below, the front of this stone,
which in effect will become the back of the grate, may be made
perfectly vertical; and the iron back of the grate being hid in
the solid work of the back of the Fire-place, will produce no
effect whatever; but if the grate be already so narrow as not to
admit of any diminution of its width, in that case it will be
best to take away the iron back of the grate entirely, and fixing
the grate firmly in the brick-work, cause the back of the
Fire-place to serve as a back to the grate.--This I have very
frequently done, and have always found it to answer perfectly
well.
Where it is necessary that the fire in a grate should be very
small, it will be best, in reducing the grate with fire-stone,
to bring its cavity, destined for containing the fuel, to the form
of one half of a hollow hemisphere; the two semicircular openings
being one above, to receive the coals, and the other in front,
or towards the bars of the grate; for when the coals are burnt in
such a confined space, and surrounded on all sides, except in the
front and above, by fire-stone, (a substance peculiarly well
adapted for confining heat,) the heat of the fire will be
concentrated, and the cold air of the atmosphere being kept at a
distance, a much smaller quantity of coals will burn, than could
possibly be made to burn in a grate where they would be more
exposed to be cooled by the surrounding air, or to have their
heat carried off by being in contact with iron, or with any other
substance through which heat passes with greater facility than
through fire-stone.
Being persuaded that if the improvements in Chimney Fire-places
here recommended should be generally adopted, (which I cannot
help flattering myself will be the case,) that it will become
necessary to reduce, very considerably, the sizes of grates,
I was desirous of showing how this may, with the greatest safety
and facility, be done.
Where grates, which are designed for rooms of a middling size,
are longer than 14 or 15 inches, it will always be best, not
merely to diminish their lengths, by filling them up at their two
ends with fire-stone, but, forming the back of the Chimney of a
proper width, without paying any regard to the length of the
grate, to carry the covings through the two ends of the grate in
such a manner as to conceal them, or at least to conceal the back
corners of them in the walls of the covings.
I cannot help flattering myself that the directions here given in
regard to the alterations which it may be necessary to make in
Fire-places, in order to introduce the improvements proposed,
will be found to be so perfectly plain and intelligible that no
one who reads them will be at any loss respecting the manner in
which the work is to be performed; -- but as order and arrangement
tend much to facilitate all mechanical operations, I shall here
give a few short directions respecting the manner of LAYING OUT
THE WORK, which may be found useful, and particularly to
gentlemen who may undertake to be their own architects, in
ordering and directing the alterations to be made for the
improvement of their Fire-places.
Directions for laying out the Work.
If there be a grate in the Chimney which is to be altered,
it will always be best to take it away; and when this is done,
the rubbish must be removed, and the hearth swept perfectly clean.
Suppose the annexed figure No. 1. to represent the ground plan of
such a Fire-place; A B being the opening of it in front, A C and
B D the two sides or covings, and C D the back.
Figure 2. shows the elevation of this Fire-place.
First draw a strait line, with chalk, or with a lead pencil,
upon the hearth, from one jamb to the other,--even with the front
of the jambs. The dotted line A B, figure 3, may represent this
line.
From the middle C of this line, (A B) another line c d, is to be
drawn perpendicular to it, across the hearth, to the middle d, of
the back of the Chimney.
A person must now stand upright in the Chimney, with his back to
the back of the Chimney, and hold a plumb-line to the middle of
the upper part of the breast of the Chimney (d, fig. 5,) or
where the canal of the Chimney begins to rise perpendicularly;--
taking care to place the line above in such a manner that the
plumb may fall on the line c d, draw on the hearth from the
middle of the opening of the Chimney in front to the middle of
the back, and an assistant must mark the precise place e, on that
line where the plumb falls.
This being done, and the person in the Chimney having quitted his
station, four inches are to be set off the line c d, from e,
towards d; and the point f, where these four inches end,
(which must be marked with chalk, or with a pencil,) will show
how far the new back is to be brought forward.
Through f, draw the line g h, parallel to the line A B, and this
line g h will show the direction of the new back, or the ground
line upon which it is to be built.
The line c f will show the depth of the new Fire-place; and if it
should happen that c f is equal to about ONE-THIRD of the line A B;
and if the grate can be accommodated to the Fire-place instead
of its being necessary to accommodate the Fire-place to the
grate, in that case, half the length of the line c f, is to be
set off from f on the line g f h, on one side to k, and on the
other to i, and the line i k will show the ground line of the
fore part of the back of the Chimney.
In all cases where the width of the opening of the Fire-place in
front (A B) happens to be not greater, or not more than two or
three inches greater than THREE TIMES the width of the new back
of the Chimney (i k), this opening may be left, and lines drawn
from i to A, and from k to B, will show the width and position of
the front of the new covings;--but when the opening of the
Fire-place in front is still wider, it must be reduced; which is
to be done in the following manner:
From c, the middle of the line A B, c a and c b, must be set off
equal to the width of the back (i k), added to half its width
(f i), and lines drawn from i to a, and from k to b, will show the
ground plan of the fronts of the new covings.
When this is done, nothing more will be necessary than to build
up the back and covings; and if the Fire-place is designed for
burning coals, to fix the grate in its proper place, according to
the directions already given.--When the width of the Fire-place
is reduced, the edges of the covings a A and b B are to make a
finish with the front of the jambs.--And in general it will be
best, not only for the sake of the appearance of the Chimney,
but for other reasons also, to lower the height of the opening of
the Fire-place, whenever its width in front is diminished.
Fig. 4. shows a front view of the Chimney after it has been
altered according to the directions here given.--By comparing it
with fig. 2. (which shows a front view of the same Chimney before
it was altered), the manner in which the opening of the
Fire-place in front is diminished may be seen.--In fig. 4. the
under part of the door-way by which the Chimney-sweeper gets up
the Chimney is represented by white dotted lines. The door-way
is represented closed.
I shall finish this chapter with some general observations
relative to the subject under consideration; with directions how
to proceed where such local circumstances exist as render
modifications of the general plan indispensably necessary.
Whether a Chimney be designed for burning wood upon the hearth,
or wood, or coals in a grate, the form of the Fire-place is in my
opinion, most perfect when THE WIDTH OF THE BACK is equal to the
DEPTH OF THE FIRE-PLACE, and the opening of the Fire-place in
front equal to THREE TIMES the width of the back, or, which is
the same thing, to THREE TIMES THE DEPTH OF THE FIRE-PLACE.
But if the Chimney be designed for burning wood upon the hearth,
upon hand irons, or dogs, as they are called, it will sometimes
be necessary to accommodate the width of the back to the length
of the wood; and when this is the case, the covings must be
accommodated to the width of the back, and the opening of the
Chimney in front.
When the wall of the Chimney in front, measured from the upper
part of the breast of the Chimney to the front of the mantle, is
very thin, it may happen, and especially in Chimnies designed for
burning wood upon the hearth, or upon dogs, that the depth of the
Chimney, determined according to the directions here given, may
be too small.
Thus, for example, supposing the wall of the Chimney in front,
from the upper part of the breast of the Chimney to the front of
the mantle, to be only four inches, (which is sometimes the case,
particularly in rooms situated near the top of a house,) in this
case, if we take four inches for the width of the throat, this
will give eight inches only for the depth of the Fire-place,
which would be too little, even were coals to be burnt instead of
wood.--In this case I should increase the depth of the Fire-place
at the hearth to 12 or 13 inches, and should build the back
perpendicular to the height of the top of the burning fuel,
(whether it be wood burnt upon the hearth, or coals in a grate,)
and then, sloping the back by a gentle inclination forward, bring
it to its proper place, that is to say, PERPENDICULARLY UNDER THE
BACK OF THE THROAT OF THE CHIMNEY. This slope, (which will bring
the back forward four or five inches, or just as much as the
depth of the Fire-place is encreased,) though it ought not to be
too abrupt, yet it ought to be quite finished at the height of
eight or ten inches above the fire, otherwise it may perhaps
cause the Chimney to smoke; but when it is very near the fire,
the heat of the fire will enable the current of rising smoke to
overcome the obstacle which this slope will oppose to its ascent,
which it could not do so easily were the slope situated at a
greater distance from the burning fuel[2].
Fig. 7, 8, and 9, show a plan, elevation, and section of a
Fire-place constructed or altered upon this principal.--The wall
of the Chimney in front at a, fig. 9, being only four inches
thick, four inches more added to it for the width of the throat
would have left the depth of the Fire-place measured upon the
hearth b c only eight inches, which would have been too
little;--a niche c and e, was therefore made in the new back of
the Fire-place for receiving the grate, which niche was six
inches deep in the center of it, below 13 inches wide, (or equal
in width to the grate,) and 23 inches high; finishing above with
a semicirular arch, which, in its highest part, rose seven inches
above the upper part of the grate.--The door-way for the
Chimney-sweeper, which begins just above the top of the niche,
may be seen distinctly in both the figures 8 and 9.--The space
marked g, fig. 9, behind this door-way, may either be filled with
loose bricks, or may be left void.--The manner in which the piece
of stone f, fig. 9, which is put under the mantle of the Chimney
to reduce the height of the opening of the Fire-place, is rounded
off on the inside in order to give a fair run to the column of
smoke in its ascent through the throat of the Chimney, is clearly
expressed in this figure.
The plan fig. 7, and elevation fig. 8, show how much the width of
the opening of the Fire-place in front is diminished, and how the
covings in the new Fire-place are formed.
A perfect idea of the form and dimension of the Fire-place in its
original state, as also after its alteration, may be had by
careful inspection of these figures.
I have added the drawing fig. 10, merely to show how a fault,
which I have found workmen in general whom I have employed in
altering Fire-places are very apt to commit, is to be avoided.
--In Chimneys like that represented in this figure, where the
jambs A and B project far into the room, and where the front edge
of the marble slab, o which forms the coving, does not come so
far forward as the front of the jambs, the workmen in
constructing the new covings are very apt to place them,--not in
the line c A, which they ought to do,--but in the line c o, which
is a great fault.--The covings of a Chimney should never range
BEHIND the front of the jambs, however those jambs may project
into the room;--but it is not absolutely necessary that the
covings should MAKE A FINISH with the internal front corners of
the jambs, or that they should be continues from the back c,
quite to the front of the jambs at A.--They may finish in front
at a and b, and small corners A, o, a, may be left for placing
the shovels, tongs, etc.
Were the new coving to range with the front edge of the old
coving o, the obliquity of the new coving would commonly be too
great;--or the angle d c o would exceed 135 degrees, WHICH IT
NEVER SHOULD DO,--or at least never by more than a very few
degrees.
No inconvenience of any importance will arise from making the
obliquity of the covings LESS than what is here recommended;
but many cannot fail to be produced by making it much greater;--
and as I know from experience that workmen are very apt to do this,
I have thought it necessary to warn them particularly against it.
Fig. 11. shows how the width and obliquity of the covings of a
Chimney are to be accommodated to the width of the back, and to
the opening in front and depth of the Fire-place, where the width
of the opening of the Fire-place is less than three times the
width of the new back. As all those who may be employed in
altering Chimneys may not, perhaps, known how to set off an angle
of any certain numbers of degrees,--or may not have at hand the
instruments necessary for doing it,--I shall here show how an
instrument may be made which will be found to be very useful in
laying out the work for the bricklayers.
Upon a board about 18 inches wide and four feet long, or upon the
floor or a table, draw three equal squares A, B, C, fig. 12. of
about 12 or 14 inches each side, placed in a strait line, and
touching each other.--From the back corner c of the center square
B, draw a diagonal line across the square A, to its outward front
corner f, and the adjoining angle formed by the lines d c and c f
will be equal to 135 degrees,--the angle which the plane of the
back of a Chimney Fire-place ought to make with the plane of its
covings.--And a bevel m, n, being made to this angle with thin
slips of hard wood, this little instrument will be found to be
very useful in marking out on the hearth, with chalk, the plans
of the walls which are to form the covings of Fire-places.
As Chimneys which are apt to smoke will require the covings to be
placed less obliquely in respect to the back than others which
have not that defect, it would be convenient to be provided with
several bevels;--three or four, for instance, forming different
angles.--That already described, which may be called No. 1. will
measure the obliquity of the covings when the Fire-place can be
made of the most perfect form:--another No. 2. may be made to a
smaller angle, d c e,--and another No. 3. for Chimnies which are
very apt to smoke at the still smaller angle d c i.--Or a bevel
may be so contrived, by means of a joint, and an arch, properly
graduated, as to serve for all the different degrees of obliquity
which it may ever be necessary to give to the covings of
Fire-places.
Another point of much importance, and particularly in Chimneys
which are apt to smoke, is to form the throat of the Chimney
properly, by carrying up the back and covings to a proper
height. This, workmen are apt to neglect to do, probably on
account of the difficulty they find in working where the opening
of the canal of the Chimney is so much reduced.--But it is
absolutely necessary that these walls should be carried up five
or six inches at least above the upper part of the breast of the
Chimney, or to that point where the wall which forms the front of
the throat begins to rise perpendicularly. --If the workman has
intelligence enough to avail himself of the opening which is
formed in the back of the Fire-place to give a passage to the
Chimney-sweeper, he will find little difficulty in finishing his
work in a proper manner.
In placing the plumb-line against the breast of the Chimney, in
order to ascertain how far the new back is to be brought
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