periments of which I am about to give an account
were made, are as follows :
.p^ f above - 1 4-93 5")
tbelow - 13.39 [ Inches, Englifh meafure.
Depth . . - - 14.52 3
It weighs 37 Ibs. Avoirdupois ; and it contains *
when quite full, about 73 Ibs. Avoirdupois, equal
to 8-J gallons (wine-meafure) of water.
In\wo Experiments with this boiler, which were
both made by myfelf, and in which attention was
paid to every circumftance that could tend to ren
der them perfeft, the refults were as follows :
end the Economy of Fust*
Experiment
Experiment
'
No. n.
No. 12.
The firft
The improved
Fire-place.
Fire-place.
Quantity of water in the Boiler,
in Bavarian pounds - - -
43.63 Ibs,
43*63 Ibs.
Temperature of the water in the
Boiler at the beginning of
the Experiment - - - -
59
60
Time employed in making the
67 mill-
/n rrjfn
Wood confumed in making the
Xw JlXllli*
water boil, in Bavarian pounds
9lbs.
3 Ibs.
Time the water continued boil-
2 hrs 2 min.
Sftonrs
*lwULi >
Wood added to keep the water
boiling ....
5lbs.
2^ Ibs.
Kind of wood ufed
Pine
Pine
Precife Refults.
Ice-cold water heated 1 80 de
grees, or made to boil, with
i Ib. of wood - - .
4.02 Ibs,
1 1.03 Ibs.
Boiling-hot water kept boiling
7w
i hour, with i Ib. of wood -
17.74105.
5 2. 3 6 Ibs.
94
Of the Management of Fir* 9
The following Experiments were made with two
Copper boilers, (No. i. and No. 2.) nearly of the
fame climenfions, in the kitchen of the Military
Academy at Munich, in the prefent improved Hate
of that kitchen. Thefe Boilers are round and deep,
and weigh each about 62 Ibs. Avoirdupois. They
belonged originally to the kitchen of the Houfe of
Induftry, being two of the eight Boilers which, in
the firft arrangement of that kitchen, were heated
by the fame Fire.
Their exact diinenfions, meafured in Englifh
inches, are as follows :
Diameter
Depth
f above i - -
1 below - - -
The Boiler
The Boiler
No. i.
No. 2.
Inches.
Inches.
22*66
22.66
19.82
20.85
24.72
22.04.
At the beginning of each of the following Ex
periments, each of thefe Boilers contained juft 95
meafures (or Bavarian maajfe) of water, weighing
187 Ibs. Bavarian weight, (equal to 232.58 Ibs.
Avoirdupois) or a trifle lefs than 28 gallons.
The grate on which the Fire was made under
each of thefe boilers is circular and concave, and
1 1 inches in diameter ; and their fire-places are in
all refpefts fimilar to that juft defcribed (Experi
ment No. 1 1 .). Both Boilers are furniflied with
double covers.
, The
and tie Economy of Fitch 95
The Experiments made with the Boiler No. i,
and their refults, were as follows :
7 xperiment'!
txperiment
txpcrimcnt
Experiment
No. 13.
No. 14.
No. 15.
No. 1 6.
Quantity of water in
j
the boiler in the
beginning of the Ex
Ibs.
Ibs.
Bn.
Ibs.
periment -
187
187
187
187
Temperature of the
water in the Boiler
at the beginning ot
the Experiment
61
59
64
551*
Time employed in
making the water
boil - - - - -
min.
73
min.
61
min.
61
min.
62
Wood confumed in
making the water
IU
n>s.
Ibs.
Ibs.
hnil
T 2
j j
g
Time the water con
i
min.
min.
min.
h. min.
tinued to boil - -
*7
2B
6
2 I 9
Quantity of Fuel add
ed to keep it boil
Ibs.
ing this time -
.*
4
Kind of wood ufcd as
Fuel - , - -
Beech
Beech
Pine
Pine
Precife Refults of the
JExperittients.
Ice-cold water heated
1 80, or made to
boil, with the heat
generated in the
,
combuftion of lib.
Ibs.
Ibs.
Ibs.
Ibs.
of the Fuel
12.89
14.15
16.89
20
Boiling water kept
boiling one hour,
with the heat gene
rated in the combuf-
fiqn of i Ib. of the
Ibs.
WOOd . r "-''"
T-
.
108.40
96 Of the Management of
All the foregoing Experiments were made on
the fame day, (the i3th of October, 1794) and in
the fame order in which they are numbered.
The following are the refolts of the Experiments
made with the Boiler Jfo. 2.
Quantity of water in the
Boiler at the beginning
of the Experiment, in
Bavarian pounds
Temperature of the wa
ter in the boiler at the
beginning of the Ex
periment -re-
Time employed in mak
ing the water boil
Wood confumed in mak
ing the water boil
Time the water continu
ed to boil
Wood added to keep the
water boiling
JCind of wood ufed r
Preclfe Rtfults.
Ice-cold water heated
1 80, or made to boil,
with i lb. of wood
Boiling-hot water kept
boiling one hour with
J lb. of waod TT TT
This fet of Experiments was made at the fame
time with the foregoing fet, namely, on the i3th
October, 1794, and they were made in the order in
which they are here regiftered- In the laft but
one, (No. 20.) the Economy of Fuel in the procefs,
of heating water was carried farther than in any
other Experiment I have ever made.
In
Exper.
No. 17.
Exper.
No. 18.
Exper.
No. 19.
Exper.
No. ao.
Exper.
No. ai.
Ibs-
Ibs.
Ibs.
Ibs.
Ibs.
187
187
187
187
187
61
58
60
55
aia*
tnin.
min.
min.
min.
75
55
57
60
M
Ibs.
Ibs.
Ibs.
Ibs.
II
II
9
8
_
min.
min.
min.
h. min.
h. min,
21
17
8
a ao
I 10
lb.
Ibs.
Ibs.
I
__ .
34:
It
Beech
Beech
Pine
Pine
Beech
Ibs.
ibs.
Ibs.
Ibs.
13.91
J4-33
I 7-J9
20.10
Ibs.
Ibs.
134.68
I4J44
and the Economy of Fuel. 97
In the following Experiments, which were made
in a large Copper Boiler fitted up on my moft im
proved principles, belonging to the kitchen of the
Houfe of tnduftry, the Economy of Fuel was car-
ried nearly as far.
This Boiler, which is circular, is 42^- Englifh
inches in diameter above ; 42.17 inches in dia
meter below; and 1 8. 54 inches deep. It weighs
78^- Ibs. Avoirdupois ; and contains, when quite
full, 714 Ibs. Bavarian weight (=884 Ibs.- Avoir
dupois, or 1 06 gallons) of water, at the tempera
ture of 55.
It is furrounded above by a wooden ring abotit
two inches in thicknefs, into which it is fitted $ and
in this ring, in a groove about -*- of an inch deep^
is fitted a circular wooden flat cover ; this cover
is formed in three pieces, united by iron hinges 5
and one of thefe pieces being fattened down by
hooks to the Boiler, the other two are fo contrived
as to be folded back upon it occaftonaily- From
the upper furface of the part of the cover which is
fattened down on the Boiler, a tin tube two inches
in diameter, furnifhed with a damper, is fixed, by
which the fteam is carried off into a narrow wooden
tube, which conduces it through an opening in the
roof of the houfe into the open air.
To prevent ftill more effectually the efcape of
the heat through the wooden cover of the Boiler,
the upper furface of it is protected from the cold
atmofphere by a thick circular blanket covered on
both fides by ftrong canvas, which is occafionally
thrown over it.
. IL O Though
98 Of the Management of Fire,
'Though the diameter of this boiler below is
more than 40 inches, the diameter of its fire-place
(which is juft under its centre) is only 1 1 inches ;
but as the flame makes two complete turns under
the bottom of the Boiler in a fpiral canal, and one
turn round it, the time required to heat it is not ib
great as, from the fmallnefs of its fire-place, might
have been expected.
It has ever been, and ftill continues to be, the
decided favourite of the cook-maids.
The wood ufed as Fuel in the following Experi
ment was pine moderately dried. Thebillets were fix
inches long, and from one to two inches in diameter.
The following Table fhows the refults of five
Experiments that were made with this Boiler by
myfelf, juft after it was fitted up :
Without
Quantity of water in the
Boiler, in Bavarian
pounds
Temperature of the wa
ter at the beginning of
the Experiment
Time required to make
the water hoil
Fuel employed to make
the water boil
Time the water conti
nued boiling
Fuel added to keep the
water boiling -
RESULTS of
the Experiments with
the heat generated in
the combuftion of I ib.
of the Fuel.
Ice-cold water heated
1 80, or made to boil -
Or boiling-hot water
kept bailing one hour -
Expcrlnt.
No. Z2.
Experim.
No. 33.
lb$.
Experim.
No.*4
Experim.
No. 15.
'Experim.
No. a6.
MM.
11)8.
Ibs.
Ib*.
508
127
254
508
508
48
h. min.
48
min.
96
h. min.
48
h. min.
4?'
h. mia.
* 4
Ibs.
51
Ibs.
I 15
Ibs.
* 35
Ibs.
3 I
Ibs.
a4
h.
*i
sa|
*5
h.
*4
Ibs.
-
Ibs.
m
4*
Ibs.
Ibs.
Ibs.
Ibs.
Ibs.
18.74
ia-74
11.69
17.48
19.01
136.61
' -.
338.66
_
an d the Ecmmy of Fuel. 99
Without flopping to make any obfcrvations on
the refults of thefe Experiments, (though thy
afford matter for feveral of an interefling nature)
I fhall proceed to give a brief account of another
fet of Experiments, on a much larger fcale, which
were made in the Copper Boiler of a Brewery be
longing to the Elector.
This Boiler, which is rectangular, is ten feet
long, eight feet wide, and four feet deep. Bavarian
meafure* and contains 8176 Bavarian maajje^ or
meafures, equal to i$6 ; 6 gallons wine meafure.
On examining this Boiler, I found its fire-place was
conftructed on very bad principles ^ and on in
quiry refpecling the quantity of fire-wood con-
fumed in it, I found the wafte of Fuel to be very
great.
This Brewery is ufed for making fmall white
beer, (as from its pale colour it is called) frorq
malt made of wheat ; and as it is worked all the
year round, the expenfe of Fuel was very great,
and the economy of it an object of confiderable
importance.
The quantity of fire-wood (pine) that had at an
average been eonfumed daily in this Brewery was
rather more than four Bavarian clafters, or cords.
On altering the fire-place of this Brewery, and put
ting a (wooden) cover to the Boiler, I reduced this
expenfe to lefs than i^ clafters.
In the new fire-place which I eaufed to be con-
ftrucled for this Boiler, the cavity under the Boiler
is
* *oo Bavarian twthcs are eaual to 95^ inches Er
IOQ Of the Management of 'Firs ',
is divided into three flues, by thin brick walls which
run in the direction 6f the length of the boiler.
The middle flue,"*Hiich is twice as wide as one of
the fide flues, is occupied by the burning Fuel, and
is furniihed with a grate 20 inches wide, and 36
inches long ; and the opening by which the Fuel
is introduced into the fire-place is clofed by two iron
doors, placed one behind the other, at the diftance
of eight inches. The grate, wi^ich is placed at the
hither end of the fire-place, is horizontal, and it is
fituated about twenty inches below the bottom of
the Boiler. The air which ferves to feed the Fire,
is let in under the grate through a regifter in the
am-pit door.
When the double doors which clofe the en*
trance into the fire-place are ihut, the flame of the
burning Fuel firft rifes perpendicularly againft the
bottom of the Boiler ; it then paffes along to the
farther end of the (middle) flue, which conftitutes
the fire-place, where it feparates, and returns in
the two fide flues ; it then rifes up into two hori*
zontal flues (one fituated over the other) which go
all round the Boiler ; and having made the cir
cuit of the Boiler, it goes off into feparate canals
(furnimed with dampers) into the chimney.
Though the Figures 17 and 18, Plate III. are not
drawings from the fire-place I am now defcribing,
but of another which I fliall foon have occafion to
defcribe, yet an infpeclion of thefe figures will be
found ufeful in forming an idea of the principles
on which the fire-place in cjueftion was conftru&ed,
and
and the Economy of Fuel. 101
and on that account I fliall occafionally refer to
them.
The burning Fuel being confined: within, a. -nar
row compafs, being well iupplied with frcfli air,
and being furrounded on all fides by thin walls of
brick, (which are jion-conduftors) the heat of the
fire is moft intenfe, and the combuftion of the
Fuel of courfe very complete. The flame, which
is clear and vivid in the higheft degree, and per
fectly unmixed with fmoke, runs rapidly along
the bottom of the Boiler, (which forms the top of
the flues) and from the refiftance it meets with in
its paffage, from friction, and from the number of
turns it is obliged to make, it is thrown into innu
merable eddies and whirlpools, and really affords
a moft entertaining fpectacle.
That I might be able to enjoy at my eafe this
amufing fight, I caufed a glafs window to be made
in the front wall of the fire-place, through which
I could look into the Fire when the fire-place doors
were fliut ; and I was well paid for the trouble and
the trifling expenfe I had in getting it executed.
Some may be tempted to fmile at what they may
think a childifh invention ; but there are many
others, I am confident, and among thefe many
grave philofophers, who would have been very
glad to have feared my amufement.
The window of which I am fpeaking is circular,
and only fix inches in diameter ; but as the hole in
the wall is conical, and much larger within than
without, the field of this window (if I may ufe the
expreflion)
102 Of the Management of Fire>
sxpreilion) -is fufHciently large to afford a good
view of what pailes in the fire-place.
: ^l>4s, conical -uo)e t is reprefented in the Figures
1 8 and 21, by dotted lines. It is fituated on the
left hand of the entrance into the fire-place. Into
the opening of the hole in the wall, on the outfide
of it, is fixed a ihort tube of copper, (about fix
inches in diameter, and four inches long) and in
this tube another ihort moveable tube is fitted, one
end of which is clofed by the circular plate of glafs
which conflitutes the window. As the wall of the
fire-place in front is thick, this pan of glafs is at a
confiderable diftance from the burning Fuel, and as
there is no- draft through the hole in the wall, the
glafs does not grow very hot.
I have been the more particular in my defcription
of this little invention, as I think it may be ufeful :
There are many cafes in which it would be very
advantageous to know exactly what is going on in
a clofed fire-place ; and this never can be known
by opening the door ; for the inftant the door is
opened, the cold air rufhing with impetuofity into
the fire-place, deranges entirely the whole economy
of the Fire : Befides this, it is frequently very dif-
advantageous to the procefs which is going on, to
open the door of a fire-place ; and it is always at
tended with a certain lofs of heat, and confequently
fhould as much as poffible be avoided.
I intimated that the window I have been defcrib-
ing afforded me amufement ; it did ftill more, it
afforded me much ufeful information ; it gave me
an
and the Economy of Fuel. 103
xn opportunity of obferving the various internal mo
tions into which flame may, by proper manage
ment of the machinery of a fire-place, be thrown ;
and of eflimating, with fome degree of precifion r
their different effects. In fhort, it made me better
acquainted with the fubject which had fo long
engaged my attention (Fire) and with regard
to that fubjed, nothing furely that is new can be
uninterefting. But to return to the Breweiy : To
the top of the Boiler was fitted a curb of oak tim
ber : The four ftraight beams of which this curb was
conflrucled are each about 7 inches thick, and 1 5
inches wide ; and the upper part of the boiler is
fattened by large copper nails to the infide of the
fquare frame formed by thefe four beams. From
the top of this curb is raifed a wooden building,
like the roof of a houfe with a double flant or bevel,
which ferves as a cover to the Boiler. This build
ing, the fides of which are about three feet high
inwards, and the top of which is covered in by a
very flat roof, flanting on every fide from the
centre, is conftrucl:ed of a light frame-work of
timber, (four-inch deal joifts) which is covered
within as well as without with thin deal boards,
which are rabbetted into each other at their edges,
to render the cover which this little edifice forms
for the Boiler as tight as poflible.
From the top of this cover, an open wooden
tube, (m. Fig. 17.) about 12 inches in diameter,
rifes up perpendicularly, and going through the
roof of the Brewhoufe, ends ia the open air. ThU
tube,
1 64 . Of the Management of fire t
tube, which is furnifhed with a wocden damper, is
intended to carry off the fleam.
On the fide of this cover next the mafhing-tub,
as alfo on that oppolite' to it, by which the wort
runs off into the coolers, there are large folding
Wooden doors, (/ and , Fig< 17.) which are occa-
fionally lifted up by means of ropes which pafs over
pullies fattened to the ceiling of the Brewhoufe.
There are likewife two glafs windows (fee
Fig. 17.) in two oppofite fides of the cover,
through which, as foon as in confequence of the
boiling of the liquid the fleam becomes tranfparent
and invifible, (which happens in a very few minutes
after the liquid has began to boil) the contents of
the Boiler may be difiinctly feen and examined.
Whenever there is occafion during the boiling to
open either a doof or a window of the cover, it is
necefTary to begin by opening the damper of the
fleam-chimney, otherwife the hot fteam, turning
out with violence, would expofe the by-ftandera
to the danger of being fcalded ; but when the
damper of the fleam-chimney is open, no fleam
comes into the Brewhoufe, though a door or win
dow of the cover be wide open.
Another fimilar precaution is fometimes necet
fary in opening the door of the fire-place, which it
may be ufeful to mention. When the dampers in
the canals by which the fmoke goes off into the
chimney are nearly clofed, (which muft frequently
be done to confine and economife the heat) if,
without altering the damper, or the regifter in the
afh-
and the Economy of Fuel* 105
aili pit door, the fire-place door be fuddenly open
ed, it will frequently happen that fmoke, and foiae-
times flame, will rufh out of the lire-place by this
pafTage. This accident may be eaiily and effec
tually prevented, either by opening the damper, or
by clofing the regifter of the afh-pit door, the mo
ment before the fire-place door is opened. This
precaution fliould be attended to in all fire-places
of all dimenfions, conftructed on the principles I
have recommended.
To economize the time and the patience of my
reader as far as it is poilible, without fuppreffing
any thing effential relating to the fubjeft under
confideration, I mail give him, in a very fmall
compafs, the general refults of a fet of Experi
ments which coft me more labour (or at leaft more
time) than it would coft him to read all the Effays
I have ever written. I believe I am fometimes too
prolix for the tafte of the age, but it mould be
remembered that the fubjects I have undertaken to
inveftigate are by no means indifferent to me ;
that I conceive them to be intimately connected
with the comforts and enjoyments of mankind ;
and that a habit of revolving them in my mind,
and reflecting on their extenfive ufefulnefs, has
awakened my enthufiafm, and rendered it quite
impoflible for me to treat them with cold indif
ference, however indifferent or tirefome they may
appear to thofe who have not been accuftomed to
view them in the fame light.
VOL. IL P ' I have
1 1>6 Of the Management of Fire,
I have already given an account, in all its va
rious details, of one Experiment which was made,
(on the 1 5th of April 1795) with the Boiler we
have juft been defcribing (fee page 78). I Ihall now
recapitulate the general refults of that Experiment^
and compare them with the mean refults of two
other like Experiments made with the fame Boiler.
Quantity of water in the Boiler -
Temperature of the water in the
Boiler at . the beginning of the
Experiment ...
Time required to make the water
boil .-
Fuel employed to make the water
boil
Time the water continued boiling -
Fuel added to keep the water boil
ing - -
Kind of Fuel ufed - - - - -
PRECISE RESULTS of the Experi
ments.
Quantity of ice-cold-water which
might be heated 180, or made to
boil with the heat generated in the
combuftion of lib. of the Fuel -
TIME in which, according to the re-
fuk of the Experiment, ice-cold wa
ter might (at Munich) be made tt
boil with the given proportion oJ
Fuel . ' *
Quantity of boiling-hot water kept boil
ing one hour with the heat generat
ed in the combuftion of i Ib. of the
Fuel
Experiment
No. 27.
Experiment
No. 28.
12,508 Ibs.
60
3 h. 40 min.
800 Ibs.
2 h. 43 min.
i oo Ibs.
Pine wood.
3 h. 48 min-
12.06 Ibs.
4h. 20 min.
339.80 Ibs.
12,508
Pine wood*
12.70 Ibs,
4h.2omin.
Oil
and the Economy of Fuel* 137
On comparing the refults of thefe Experiments
with thofe made in the Boilers of the kitchens of
the Houfe of Induftry and Military Academy, I
was led to imagine that either the Boiler, or the
fire-place of the Brewery, or both, were capable
of great improvement ; for in fome of the Experi*
nients with thefe fmall kitchen Boilers., the Eco
nomy of Fuel had been carried fo far, that with
the heat generated in the cornbuftion of i Ib. of
pine- wood, it appeared that 20 Ib. of ice-cold
water might have been made to boil ;-r ^but here,
though the machinery was on a fcale fo much larger,
(and I had concluded, too raflily indeed, as will be
fliown hereafter, that the larger the boiler the
greater is of courfe the Economy of Fuel) the
refults of thefe Experiments indicated, that not
quite 13 Ibs. of ice-cold water could have been
made to boil with the heat furnilhed in the corn
buftion of i Ib, of the wood.
The Experiments, No. 22, No. 25, and No. 26,
which were made with the largeft of my kitchen
Boilers, had, it is true, afforded grounds to fufpecl
that, beyond certain limits, an increafe of fize in
a Boiler does, not tend to diminifli the expenfe of
Fuel in the procefs of heating water j yet, as all
my other Experiments had tended to confirm me
in the opinion I had, at an early period, imbibed on
that fubjeft, I was difpofed to fufpect any other
caufe than the true one of having been inftru-
mental in producing the unexpected appearances I
obferved,
I
Of the Management of Fire,
I was much difappointed, I confefs, at finding
that the Brewhoufe Boiler, notwithflanding all the
pains I had taken to fit up its fire-place in the moil
perfect manner, and notwithstanding its enormous
dimenfions, when compared with the boilers I had
hitherto ufed in my Experiments, fo far from an->
fwering my expectations, actually required confi-
derably more Fuel, in proportion to its contents,
than another Boiler fitted up on the fame prin
ciples, which was not one fiftieth part of its fize.
This unexpected refult puzzled me ; and I
muft own that it vexed me, though I ought per-
haps to be aftiamed of my weaknefs ; but it did
not difcourage me. Finding on examining the
Boiler, that its bottom was very thick, compared
with the thicknefs of the {heet copper of which my
kitchen Boilers were conflructed, it occurred to
me that poffibly that might be the caufe, or at leaft
one of the caitfes, which had made the confumption
pf Fuel fo much greater than I expected ; and as
there was another Brewhoufe in the neighbour
hood belonging to the Elector, which, luckily for
me, flood in need of a new Boiler, I availed my*
felf of that opportunity to make an . Experiment,
which not only decided the point in queftion, but
alfo eitablimed a new fact with regard to heat,
which I conceive to be of confiderable importance,
Having obtained the Elector's permiflion to ar
range the fecond Brewhoufe as I mould think beft,
I determined to fpare no pains to render it as per
fect as poflible in all refpefts, and particularly in
every
and the Economy of Fuel. 109
every thing relating to the Economy of Fuel. As