CERTAIN IMPROVEMENTS ON OR ADDITIONS TO BOILERS, APPLICABLE TO VARIOUS USEFUL PURPOSES
Year: 1834

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEAN,
JACQUES LEOPOLD OBERLIN, of Leicester Square, in the County of Middlesex,
Merchant, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,.
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eighteenth day of January, in the fourth year of His reign,
did, for Elimself, His heirs and successors, give and grant unto me, the said
Jean Jacques Leopold Oberlin, Eis especial licence, full power, sole privilege
and authority, that I, the said Jean Jacques Leopold, my exors, adñiors, and
assigns, or such others, as I, the said Jean Jacques Leopold Oberlin, my exors,.
adiiors, or assigns, should at any time agree with, and no others, from time to
time and at all times during the term of years therein expressed, should and.
lawfully might make, use, exercise, and vend, within England and Wales, and
the Town of Berwick upon Tweed, the Invention of "CERTAIN IMPROVEMENTS
ON OR ADDITIONS TO BOILERS, APPLICABLE TO VARIOUS USEFUL PURPOSES," communi-
cated to me by a certain foreigner residing abroad; in which said Letters
Patent is contained a proviso, that I, the said Jean Jacques Leopold Oberlin,
shall cause a particular description of the nature of the said Invention, and in
what manner the same is to be performed, to be inrolled in His said Majesty's
High Court of Chancery, within six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by the same,
reference being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Jean Jacques Leopold Oberlin, do hereby declare that the nature of the said
Invention, and the manner of carrying the same into effect, are described as
follows, that is to say:
The object of the said improvements on or additions to boilers applicable to
various useful purposes is to cause any given temperature within certain limits
to be maintained in particular vessels or places. The said improvements are
particularly applicable to boilers used for boiling water for culinary purposes;
but they may be applied to boilers wherein a fluid is required to be heated to
a lower or to a higher temperature than that of boiling water; and they are
also applicable in many situations, such as hot-houses, or workshops, or private
apartments, for regulating and maintaining at a given point the temperature
thereof. They consist in certain apparatus so contrived that parts thereof
shall be acted upon and put in motion by the ebullition of fluids, and occasion-
ally by the expansion of air combined therewith or alone. The motion thus
produced, being applied to close or open apertures, in order to cut off or permit
the entry or escape of the draught or current of air which supplies the furnaces
of the boilers, or the ovens or buildings in which the said improvements are
applied. In applying the said improvements to boilers used for boiling water
for cooking, the cbullition of the water itself, or other fluid boiled therein, acts
directly upon floats, which are so connected with the chimney of the furnace
belonging to the boiler, that in rising, such floats cut off the draught of the
furnace, and in sinking they reopen it.
But in apparatus constructed with the said improvements to regulate or
govern the temperature of boilers used as hot water boilers, for supplying baths,
or for any purpose not requiring the water to reach the boiling point, or in
applying the said improvements to regulate the temperature of the air in work-
shops, or hot-houses, or ovens, the apparatus may be constructed to act by the
expansion of air; or it may be constructed to contain within itself some fluid
which will boil at that particular temperature which it is desired to maintain
uniformly, whether the same be below or above two hundred and twelve
degrees of Fahrenheit; and the apparatus or a part of it is placed in or in
communication with such boiler or oven, or workshop or other building, so that
the temperature thereof will communicate itself to the fluid contained in the
apparatus, and will cause it to boil and generate vapor whenever that tempe-
rature passes the desired point. The ebullition of the fluid acts, as I will
berein-after more minutely explain, to give motion to the apparatus, or to a
part of it, and that motion may be communicated to a damper or register
placed in the flue through which air is supplied or allowed to escape, eitlier

page_text: to cut off the ingress of cold air, or to permit the escape of hot air, as the case
may be.
For the mere complete explanation of the said improvements, I have here-
unto annexed two Sheets of Drawings, whercon the Figures delineated in
Sheet I. represent a complete cooking apparatus, with a furnace and boiler,
furnished with the aforesaid improvements or additions.
Figures 1 and 2, Sheet 2, shew another form of cooking apparatus, with
regulating apparatus applied to the boiler.
Figures 3 and 4, Sheet 2, shew apparatus which may be applied in a build-
ing or be attached to a boiler; and Figure 5, Sheet 2, shews an apparatus
constructed according to the said improvements, adapted more particularly to
regulate the temperature of a building or room which may require a varying
temperature, such as a hot-house or a workshop.
In Figures 1 and 2, Sheet 1, A, A, is the boiler. In one half of it is placed
a cylindrical vessel B, B, which is the fire-place or furnace, with holes cut in
its upper end to serve as a chimney to let out the air which has supplied the
combustion. A charcoal fire is made on the grate C, which stands on feet in
the bottom of the furnace, see the plan; out of the lower part of the furnace
grows a chamber D, from which a pipe E rises, see also Figure 3, which is a
detached view of the furnace, shewing the pipe E and regulating float in
section; holes are cut round the upper part of that pipe to admit the external
air which enters the furnace through the passage D, passes up through the
fucl laid on the grate, and out at the upper end of the furnace B, so as to keep
up a proper draught. F is a tube fitting loosely on the pipe E, to the lower
end of which is soldered an inverted cup G, which rests on the chamber D.
The upper part of the tube F, comes up close to the air holes of the pipe E,
but does not cover them. The apparatus is prepared for working, as follows:-
The fire being lighted, the boiler is nearly filled with water which surrounds
the furnace and the pipe F, covering and rising above the inverted cup or
float G. The air contained therein is driven out as the water rises from the
upper part of the cup, through a small rising pipe h, the top of which is closed
by a conical tight fitting plug c, as soon as the boiler is sufficiently filled; the
water then stands up in the pipe h, to the same level as in the rest of the
boiler; a cover is then put over the furnace. The lid d, d, which is soldered to
the furnace B, B, and fits over one half of the boiler, is fastened close down
thereon by little sliding bolts at e, which enter the sides of the boiler, and another
lid is put over the other half of the boiler at ff; a small lid is also put over
the aperture which is left in the cover d, d, to take out and put in the regu-
lating floater G; see the shape thereof in the plan Fig. 2. The lids should fit

page_text: well together so as to prevent the free escapo of steam; but it is not meant
that they should resist the pressure of strong steam.
Note. When meat or vegetables or other things are to be boiled in the
water, a perforated plate El is put into the boiler, across it, to serve as a guard,
to prevent the meat or other substance from pressing against the float G, and
disturbing its action. The plate E slides up and down in grooves, see Fig. 1
and 2. and the water can circulate freely through it. The apparatus is now
ready to operate; as soon as the water begins to boil, and steam is formed, it will
rise up in the pipe h, as well as in the body of the boiler, and in a very short
time (as it cannot escape out of the boiler as fast as it will be formed), it will
fill the upper part of the pipe h, and reacting against the surface of the water,
it will press against the stopper of that pipe; or if there be any air stopper left
therein, it will compress the air and will lift up the float G. The upper part
of the pipe F, will in rising cover partially or wholly, (according to the space
it is moved through,) the draught holes in the pipe E, whereby the draught of
the furnace being partially or wholly checked, the heat will instantly diminish,
and in a very short time the generation of steam in the boiler will cease. The
upper part of the regulator G, h, being then no longer filled with elastic
vaper, it will drop down again into its former position, and thus uncover the
draught holes of the pipe E; the draught being then renewed, the heat will
again be increased, and ebullition and the generation of steam may again tako
place in the boiler; and whenever it does, and steam is generated in any
quantity, the regulating float G, h, will operato as above described, and again
check the draught.
The parts that compose the regulator will act, therefore, to prevent the heat
of the fire from urging the water or other fluid beyond boiling point, that is to
say, they will always prevent its boiling over or producing steam rapidly for as
many hours as it may be requisite for the meat or vegetables or other matters
to remain in to be properly cooked, without the necessity of any person watch-
ing the operation.
To the boiler are attached several cooking vessels, for the sake of making a
complete and convenient cooking apparatus, see Fig. 4, which is an external
view of the apparatus put together. These I will describe briefly, but they
form no part of the aforesaid improvements, which, as applied to boilers used
for cooking, consist entirely in the parts which I have described as being
operated upon by the vapour of the boiling fluid to check the draught of the
furnace whenever such vapor is formed.
I, Figure 5, is a vessel which may be placed over the furnace B for roasting
or baking meat; the cylindrical neck fitting over the mouth of the furnace,

page_text: the heated air from the furnace passes through the passage or dripping pan i,
which draws out, and through holes in the bottom of the vessel whereon the
ineat is placed, also through a passage shewn by dotted lines at m; the hot
air thus passes over and under the meat, and escapes through an aperture at n,
made in the cover of the vessel.
one.
J, L, are two vessels for steaming vegetables, one or both of which may be
used at once. If both are used, the upper one serves for a cover to the under
The steam from the boiler passes up into the lower one through a pipe
in the bottom of it, and thence through another pipe into the upper one. Mis
a vessel for stewing, to be placed over the furnace in lieu of the roaster I,
and N, Fig. 6, is a kettle, which may be put over the furnace to boil water, if
it is not wanted for other purposes.
In the apparatus drawn in Figures 1 and 2, Sheet 2, the parts have so
nearly the saine operation as in the apparatus just described, that it will be
sufficient to point them out. The furnace B is mounted in a second and
larger cylinder or case A, A, the annular space between the two serving as a
reserve boiler to keep hot water in for washing or other purposes. D is a side
pipe formed at one side of the furnace, see the plan, opening into it under the
grate C. The current of air for supporting combustion comes in through the
side pipe D, passes up through the fuel laid on the grate C, and thence away
up through the chimney E, at the upper part of which a hole is cut at a to let
it escape. G is the boiler; it is a cylindrical vessel, see the plan, mounted
in the furnace, resting on a bead formed round the upper part thereof. His
the inverted cup or regulating float, furnished with a small pipe J to let the
air escape from the inverted cup when the boiler is filled; to the regulating
float is attached, by a stem, a ring or piece of tube at I, which surrounds the
chimney just below the open part a thereof. The operation of this apparatus
is just the same as that of the apparatus Sheet I., and the instructions herein-
before given in reference to that apparatus must be attended to in setting it to
work, videlicit, whenever the water or soup in the boiler passes the boiling
point, and a quantity of steam is generated, the regulating float H rises (by
reason of the pressure of the steam in the upper part of the float and its pipe
J), and the ring or tube I covers over partially or entirely the apperture in the
chimney E, hence the draught of the furnace is checked, and the heat dimi-
nishing, the boiling of the fluid ceases, the regulating float falls and uncovers
the draught hole of the chimney E, by which operation the fluid contained in
the boiler is prevented without any overlooking, as I have described in refer-
ence to the Figures in Sheet 1, from boiling over. K is the guard put into
the boiler, to keep the eatables. cooked therein from touching the regulator.

page_text: I is a steaming vessel, with a pipe M to let the steam from the boiler pass
into it; to steam vegetables, another such vessel may be put over it, as in the
apparatus, Figures 1 and 2. Figure 3, Sheet 2, represents an apparatus
adapted to regulate the temperature of a boiler for supplying hot baths, or of
an oven, a hot-house, or a workshop. It is a bent or syphon tube H, G, one
leg of which is open to the atmosphere, with a large mouth at A, and the
other leg terminates in a bulb B. The bulb B and the bent tube are filled with
fluid (say water) until it stands up to a certain height in the leg 11, the air
being displaced in filling the apparatus. C is a float, immersed partly in the
fluid in the leg H, suspended by a chain passing over two pullies 1 and 2,
the other end of which chain is attached to the damper of the flue, if the appa-
ratus be attached to a boiler, or to a valve or window or trap door, if it be
applied to an oven or building. Before setting such an apparatus to
work, it must bo ascertained by experiment at what particular temperature
the fluid contained in it will boil, and that being done, it must be placed so
that the whole apparatus, or at least the upper part of the leg G, and the bulb
B, are exposed to the temperature of the place, the temperature of which it is
desired to regulate. Whenever that temperature rises above the boiling point
of the fluid contained in the apparatus, steam will be generated in the bulb B,
which will press upon the surface of the fluid therein, and cause it to rise in
the leg II, consequently the float C will rise, and the damper will descend and
close wholly or partially the flue of the furnace. If the apparatus be intended
to act by letting out hot air from the place in which it is; as, for instance, if it
be applied to the interior of a hot-house, then the rising motion of the float
must be transmitted so as to open or lift up a valve or a window or door when-
ever the temperature rises too high. To render the same apparatus available as
a regulator for different temperatures, different fluids may be used in it, which
boil at different temperatures, as for instance, for temperatures above 212 de-
grees of Fahrenheit, solutions of salt and water or of muriate of lime or of
sulphuric acid may be used, the proportion of the salts or other matters dis-
solved in the water being varied according to the temperature at which the
solution is desired to boil. For regulating temperatures below 212 degrees of
Fahrenheit, other fluids, such as alrohol or ether, which boil at very low tem-
peratures, may be used, pure or mixed with fluids of a higher boiling tempera-
ture, care being taken only, as I have already stated, to ascertain correctly, by
trial before setting the apparatus to work, the particular temperature at which
the fluid (whether pure or mixed) contained in it will boil. And note also:-The
same fluid may be made to answer the purpose of a regulator for several tem-
peratures in an apparatus of this kind, by subjecting it to various degrees of

page_text: pressure. This may be done, as shown in the Figure 4, Sheet 2, where the
regulating fluid, instead of communicating directly with the float C, acts
thercon through the medium of a column of mercury. According to the
difference between the height of the column in the ieg G and the height of the
column in the leg II, the pressure on the regulating fluid in the bulb B may
be reduced or increased, and hence as fluids boil at different temperatures
under different degrees of pressure, the same fluid at B, as, for instance, water,
may be made to answer the purpose of a regulator for various degrees of tem-
perature, by varying the proportion between the heights of the columns of
mercury in H and G.
Figure 5, Sheet 2, is a view of an apparatus adapted more particularly for
regulating the atmosphere of an oven, or a hot-house, or a workshop, to a
given temperature; this apparatus acts like the former, by the ebullition of
a fluid, but the ebullition acts directly on the instrument itself, and the motion
of the instrument is transmitted to the damper, or valve, or other register,
without any intermediate floater. The apparatus, Figure 5, consists of a
vibrating or oscillating tube A, A, with a bulb formed at each end thereof.
It is filled with mercury, so as to fill the bulb C about two thirds full, leaving
the other one about one third full. The remaining third of the bulb C
contains the regulating fluid (water for instance); the bulb B is open to the
atmosphere, but the bulb C, after the apparatus is filled and the air has been
expelled from the bulb, is closed tight by a plug or stopper a. The tube A, A,
is carried by a socket or screw clamp D, in which it can be slided backwards
and forwards and fixed at any part by the clamp screw E. The socket D is
suspended on a pivot by a pair of links F, fastened to a fixed bracket G.
II is a sliding socket, from which the damper is suspended by a chain or
cord 2. Or, if the motion of the apparatus is to unclose an aperture, the
chain 2 will be connected accordingly with a valve or window or door, so as to
open the same. The socket II can be set fast at any part of the tube A, A,
by the screw I. L, L, is a scale divided into degrees corresponding to the
different temperatures at which some particular fluid boils under different
pressures, and with reference to the differences between the levels of the
mercury in the two bulbs B and C, that will be produced by turning the
tube A, A, about its pivot or centre of motion, for it is clear that the nearer
the tube A is turned towards the perpendicular line the greater will be the
height of the column of mercury pressing on the fluid at d, and vice versa;
but by sliding the tube backwards or forwards in its socket D, and sliding the
socket G backwards or forwards, if requisite, the two arms of the vibrating
tube A may be kept in equilibrio, notwithstanding the variation of pressure on

page_text: the fluid d. An index K is attached to the tube A under the bulb C. Now,
the divisions on the scale being graduated experimentally, to indicate what
pressure is exerted on the fluid d for each particular obliquity of the vibrating
tube A, and each division marked with the temperature at which the fluid will
boil when under such pressure, the mode of operation of the apparatus will
be as follows:-To set it for regulating any particular temperature within its
range, all that is requisite is to move the tube A about its ccutre of motion,
until its index points to the division on the seal indicating that temperature.
The tube will then be slided one way or other in its socket, till its two arms
are in equilibrio or nearly so, the end C having a very small preponderance.
The two screws E and I are then set fast, and a pin is put into one of the
holes in the scale under the end of the tube to support it. The fluid d
will then be under the pressure of such a column as will cause it to boil at
the temperature at which the index K stands; so soon, therefore, as the tem-
perature of the place in which the apparatus is placed exceeds that pointed to
by the index the fluid at d begins to boil. The elastic vapour evolved presses
on the surface of the mercury in C, and drives it up into the bulb B, which,
therefore, causes that arm of the oscillating tube to preponderate and descend,
dropping with it the chain 2, which will act on the damper or valve to which
it is connected to diminish the temperature, either by cutting off the draught
of the heating furnace, or allowing the hot air of the place to escape, or
allowing fresh and cold air to enter, according as the apparatus is applied.
As soon as the heat subsides, the boiling of the fluid d will subside, the
mercury will flow back from B to its old level in the bulb C, which will
descend and lift up the chain 2 again, to re-establish the current as it was
before, and thus the temperature will be kept uniformly at the same point.
Note: Instead of the tube being moveable in the sockets D and I, it may be
fixed therein, and a ring, sliding on the tube between D and the bulb C, will
answer the purpose for balancing the opposite arm at any desired oblique
position of the apparatus, so as just to keep the end C down upon the pin
that is put into the scale at any particular division, but to allow a very small
force to move the apparatus about its centre of motion. And note also:-
A scale may be applied to an apparatus of the form shewn in Figures 3 and 4,
as well as to the apparatus Figure 5, each degree or division corresponding to
the pressure exerted on the regulating fluid in B, when the column of mercury
in 11 stands at a particular level, and such degree being marked with the tem-
perature at which the fluid will boil when under that pressure. The range of
either of these apparatus when intended to act by a varying pressure on the
regulating fluid, will be governed by the height of the columns of mercury

page_text: used. If in the leg G, Figure 4, Sheet 2, the column be sufficiently high to
balance the pressure of the atmosphere on the surface of the mercury in the
leg H (as in a barometer), the fluid at B may boil in vacuo, and by increasing
then the height of the column in H, the pressure on the fluid may be
increased up to or beyond the atmospheric pressure; according, therefore, as
the apparatus is to be used for temperatures under 212 degrees of Fahrenheit
or above them the lengths of the legs H and G will be settled; and so in
respect to the apparatus, Fig. 5, Sheet 2; its range will be determined by the
height of the column of mercury that can be obtained at a, convenient
obliquity of the apparatus, and will depend therefore on the length of the
radius of its armis. The elasticity of atmospheric air may be also employed
in applying the aforesaid improvements by introducing some air with the
regulating fluid. In the apparatus, Fig 3, 4, and 5, Sheet 2, the air will be
introduced with the regulating fluid in the bulbs B or C in Figure 5, and in
the cooking apparatus, Sheet I., and in Fig 1 and 2, Sheet 2, air will
be allowed to remain in the pipes h and J, and under the inverted cups,
by keeping the plugs in while the boiler is being filled. The expansion of the
air contained in the said bulbs, or in the inverted cups, when it becomes
heated, will act as well as the vapour produced by the ebullition of the fluid to
raise the floats or to turn the apparatus, Fig. 5. about its centre of motion; and
in some cases, it may be advantageous to make an apparatus to act entirely by
the expansion of air for regulating temperatures; as for instance, regulating
the temperature of an oven for hatching eggs by artificial heat, which requires
about 32 degrees of Reaumur, or about 72 degrees of Fahrenheit. I apply a
regulating float, Figure 6, Sheet 2, (on the plan of the floats described in
reference to boilers for cooking,) which is placed in a vessel containing water,
leaving the upper part of the inverted cup (a) filled with air. This regulating
apparatus is placed, either in the oven, or where it will partake of the tempera-
ture thereof. The air in the upper part of the float a, expands as the air and
water surrounding it become heated, and the float is adjusted to act on the
chimney of the oven to cut off the draught (as I have described in reference
to Sheet 1), as soon as the air in or coming from the oven which surrounds
the regulating apparatus exceeds 32 degrees of Reaumur; a regulating appa-
ratus of this kind may act upon a damper pipe to close the chimney of the
oven (as in the cooking apparatus herein-before described), or by means a
damper suspended by a chain (as described in reference to the other appa-
ratus), as the case may require. But note:-The adjustment of such an
apparatus will be made by varying the length of the damper pipe, or the
length of the chain that suspends the damper; for the float will begin to rise

page_text: or move a little as soon as ever the air becomes heated; and the length of the
damper pipe attached to it that closes the chimney, or of the chain that
suspends a damper must be such, that the rising of the float will not operate
to begin to cut off the draught until the heat of the oven has passed the desired
temperature. The float must therefore be adjusted by trial whenever it is
intended to keep the oven at a temperature different from that usually
employed. The same observation as to adjustment must be kept in mind
whenever the expansion of air is employed in any of the apparatus herein-
before described; that is, the length of the damper pipes, or of the chains of
the dampers must be such as to allow for the motion produced by the ex-
pansion of the air before the required temperature has been acquired by the
boiler, oven, or other place; and in respect to using the expansion of air, it
must be observed, that the expansive force of air by heat is very small at low
temperatures, and consequently would be insufficient when a considerable
amount of force is requisite to overcome the resistance of the damper or valve.
Also the force resulting from the expansion of air comes into existence and
subsides slowly and gradually, whereas the force resulting from the ebullition
of fluids as herein-before described, does not begin to show itself till a parti-
cular moment, and then comes into existence almost instantaneously, and is
destroyed again as rapidly. It will only, therefore, be in particular cases, which
must be left to the discretion of the maker of such apparatus, that it will be
adviscable to make them to operate by the expansion of air. It would be
impossible in respect to the application of the improvements herein-before
described, to lay down more than the general rules that I have given for the
proportion and adjustment of their several parts, as they will require to be
varied according to the situation in which the apparatus is to be placed &
the objects it is intended for. The maker of such apparatus must therefore
exercise some discretion in selecting which kind of the apparatus described is
best fitted for his particular purpose, and whether to adapt it for regulating
different temperatures by using different regulating fluids, or by using the same
regulating fluids and varying the pressure thereon, by means of an intermediate
column of fluid, as I have described, or when to use the expansion of air, and
in all cases, any of the apparatus should be adjusted experimentally, according
to the result it is intended to produce before setting it to work; but particu-
larly when the same apparatus is intended to act to regulate different
temperatures, by means of a varying pressure on the fluid, and has a scalo
attached to it, the scale must be graduated experimentally, with reference to
that particular apparatus, and the particular degrees of pressure under which
the regulating liquid used therein will boil at the several temperatures to which

page_text: it is intended to confine the boiler, or oven, or building, to which such appa-
ratus is applied. That being once done by the maker, the person using the
apparatus, will afterwards be able to set it, to regulate for any temperature
within its range, by following the directions herein-before given.-And note:
When it is desired to regulate the temperature of a given place very exactly, it
should be heated by means of an intermediate body of hot water, or steam, or
hot air, and not directly by the furnace itself, because the latter may accumu-
late a great quantity of heat, and so continue to increase the heat of the place,
whose temperature it is desired to keep at a given point long after the regu-
lator has caused the flue to be closed; and then the regulator, instead of being
applied directly to act upon the boiler or other place, whose heat is to be kept
uniform, should be applied to act upon the intermediate body of steam or hot
water, or hot air, by shutting a valve or damper so as to shut off the supply of
hot air or steam, or hot water, whenever the temperature of the place rises too
high, and reopening it to admit a fresh supply when the temperature has
subsided.
In conclusion, I hereby declare, that under the Patent granted to me as
berein-before stated, for Certain Improvements on or Additions to Boilers,
applicable to various useful Purposes, I do not claim generally the application
of the force of vapour arising from the ebullition of fluids, or of the force
arising from the expansion of heated air, such general application being well
known and having been made in particular cases; but I do claim the
several kinds of apparatus that I have herein-before described, in reference to
the two Sheets of Drawings annexed, for regulating the temperature of the
fluids heated in boilers used for cooking, and for regulating the temperature of
hot water boilers, ovens, workshops, and other buildings; the said apparatus
being capable of being adjusted for regulating different temperatures, as I have
described, by using different regulating fluids which boil at different tempera-
tures, or by varying the pressure on the same regulating fluid, by means of an
intermediate fluid of sufficient density to cause conveniently such pressure, or
by varying the adjustment of the parts that transmit the motion of the regu-
lating floats to the damper pipes or dampers that intercept the draught of the
furnace; and as to the proportions of the several apparatus, they may be
varied according to the purpose they are made for, keeping in view the pro-
perties which I have stated as being essential to them.
In witness whereof, I, the said Jean Jacques Leopold Oberlin, have here-
unto set my hand and seal, this Eighteenth day of July, in the year
of our Lord One thousand eight hundred and thirty-four.
J. J. L' OBERLIN. (L.S.)

page_text: AND BE IT REMEMBERED, that on the Eighteenth day of July, in the
year of our Lord 1884, the aforesaid Jean Jacques Leopold Oberlin,. came
before our said Lord the King in His Chancery, and acknowledged the Speci-
fication aforesaid, and all and every thing. therein contained and specified, in
form above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Eighteenth day of July, in the year of our Lord One
thousand eight hundred and thirty-four.