CERTAIN IMPROVED METHODS OF PRODUCING OR MANUFACTURING CERTAIN INFLAMMABLE SUBSTANCES, AND OF APPLYING THE HEAT AND LIGHT OBTAINED FROM CERTAIN INFLAMMABLE SUBSTANCES TO VARIOUS USEFUL PURPOSES
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
CRUCKSHANKS, of. Liverpool Street, New Road, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Third day of July, in the third year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Alexander
Cruckshanks, Her especial licence, full power, sole privilege and authority,
that I, the said Alexander Cruckshanks, my exors, admors, or assigns, or such
others as I, the said Alexander Cruckshanks, my exors, adfors, 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 mentioned, should and lawfully might
make, use, exercise, and vend, within England, Wales, and the Town of
Berwick upon Tweed, and also in all Her said Majesty's Colonies and Plan-
tations abroad, my Invention of "CERTAIN IMPROVED METHODS OF PRODUCING OR
MANUFACTURING CERTAIN INFLAMMABLE SUBSTANCES, AND OF APPLYING THE HEAT
AND LIGHT OBTAINED FROM CERTAIN INFLAMMABLE SUBSTANCES TO VARIOUS USEFUL
PURPOSES;" in which said Letters Patent is contained a proviso that I, the said
Alexander Cruckshanks, shall cause a particular description of the nature of
my said Invention, and in what manner the same is to be performed, to be
inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
l'atent, as in and by the same, reference being thereunto bad, will more fully
and at large appear.

page_text: NOW KNOW YE, that in pursuance of the said provision of the said
herein-before in part recited Letters Patent, and in compliance therewith, I,
the said Alexander Cruckshanks, do hereby declare that the nature of my said
improved methods consists generally in producing or manufacturing liquid
tar from coal, and an inflammable gas from the decomposition of water, in a
more economical and efficient manner than heretofore used, and in certain
new and advantageous arrangements for applying to various useful purposes
the heat and light to be obtained from such liquid tar, from such inflammable
gas, and from oils, alcohol, and other inflammable substances, existing either
naturally in a fluid state, or capable of being reduced by heat to that state;
and I declare that the manner in which the said improved methods are to be
carried into effect, that is to say:
The new processes of which the said improved methods consist are par-
ticularly set forth and explained in and by the following description thereof,
and in and by the Drawings hereunto annexed as illustrative of certain parts
thereof:-
And I declare that the first of my said improved methods, which are six in
number, relates to the producing or manufacturing of liquid tar from coal.
By the usual method of distilling tar from coal in close vessels, the inflam-
inable gas evolved in the process is allowed to escape into the atmosphere;
whereas by my said improved method the gas is made to pass from the appa-
ratus in which the tar is collected. to the furnace for heating the distilling
vessel, where it becomes ignited, and furnishes a large auxiliary supply of heat,
or it is collected in reservoirs and applied in aid of the heating of other sepa-
rate distilling vessels. When the gas so obtained is in sufficiently large quan-
tities, it may be made use of by itself without combination with any other
inflammable substance to heat the distilling vessels; but in that case I substi-
tute for the coal or coke commonly employed in the furnace a quantity of
broken fire brick or other incombustible material, and pass the gas (previously
ignited), through the same, along with a regulated and proportionate supply of
atmospheric air; whereby the mass of broken fire brick or other incombustible
material is soon made red hot, and kept steadily at that temperature as long
as the supply of gas, and a proportionate quantity of atmospheric air, is kept
up.
And whereas there are some descriptions of coal which do not posses:
the property of caking or cohering when subjected to heat, and from which,
of consequence, tar cannot be profitably distilled, as the residuum would be of
no value as fuel; now, in order to avail myself of all such descriptions of
coal, and so to obtain a valuable product from what has been hitherto
regarded as mere waste or refuse, I mix with any quantity of small coal of

page_text: the above description a suitable quantity of small caking coal, whereby the
two descriptions of coal become, during the process of distillation, agglutinated
into a solid mass or masses. The portions in which the two sorts of coal may
be best combined depend on the degree of composition to fusion possessed by
the caking coal, and this may vary so considerably that it is only by trials (of
which a few on a small scale will suffice) that the exact proportions can in each
case be determined.
The second of my said improved methods relates to the obtaining an
inflammable gas from the decomposition of water; and for the better under-
standing thereof I refer to Figure 1 of the Drawings hereunto annexe<l,
which is an elevation in section of an apparatus suitable for the purpose.
matter.
A represents an ordinary boiler for generating steam, with the float and
other appendages left out; B, hot-water cistern for supplying the boiler
C, cold-water cistern, supplied by a pipe with a ball-cock from a reservoir
at a higher level; D, a retort, standing on a strong cast-iron plate, and
filled with coke, charcoal, charred peat, anthracite, or other carbonaceous
E, a pipe through which the steam flows from the boiler; F,
a pipe through which the gas passes from the retort; G, a chamber for
charging the retort; H, fire-place; I, I, hoppers for introducing fuel ;
K, fire grate; L, ash pit; M, apertures, shewn by dotted lines, for admitting
air to the fire-place. There should be one or more ranges of these apertures
at different heights, according to the depth of fuel required; and they should
be furnished with registers to regulate the draught. By thus introducing air
at different heights, a uniform temperature is maintained, and the formation of
clinkers by the intense heat in the lower stratum of the fuel, when all the air
is admitted by the grate, as is usually the case, is prevented. N, pipe by
which any refuse matter falls from the retort into the cistern O; P, box for
receiving the refuse; Q, flue through which the hot air from the furnace
passes to the boiler and hot water cistern; R, flue leading to the chimney.
When an apparatus such as I have herein-before described is at work, the
steam from the boiler, flowing through the pipe E, is partially heated by the
hot air which passes from the furnace under the boiler; it is further heated
in the body of the furnace, and it at length enters the retort at a red heat,
the lower part of the pipe E being surrounded by the burning fuel. To
nake sure of the steam being rendered red hot, I recommend that the pipe
should be of a flat elliptical form; and where the quantity of steam is large,
instead of using one pipe I prefer making use of several small pipes, it
being essential that the extent of heating surfaces should be in proportion to
the quantity of steam passed through in a given time. The extent of heating

page_text: surfaces may be further enlarged by the introduction into the pipe or pipes of
broken pieces of fire brick, or any other similar means. The pipe F, through
which the gas issues at a red heat from the retort, passes through the boiler,
and the heat which is given off together with that communicated to the hot
air from the furnace suffices to generate the steam required without an addi-
tional fire. The pipe F is continued through the cistern B, beyond which it
is enclosed in the pipe S. This outer pipe is supplied with cold water by
another pipe from the cistern C, which entering at T, and rising to the hot
water cistern, gradually abstracts the heat from the descending gas in E, which
arrives cold at U, whence it is conducted to a lime vessel or gasometer.
To introduce the decomposing material into the retort, the sliding plate V
(which must be ground flat and accurately fitted on its bed) is pushed
forward, as shewn in the Drawing. The cover W is then removed, the
chamber filled, and the cover replaced as quickly as possible. The sliding
plate is then immediately drawn back within the brickwork. To prevent
air from entering the retort during the removal of the refuse from the
pipe M, its lower end is immersed in the water of the cistern N. The
refuse is drawn out from time to time into the box P, which when filled is
removed and emptied. The water joint of the pipe M is shewn in the
Drawing in its simplest form; but for greater security against accidents, the
opening for refusing the refuse may be secured by a door or shutter, which
will prevent the entrance of air, should the water from leakage or other
accidental cause fall below the proper level. The apparatus which I have
now described will answer perfectly where one retort is used. But two
or more retorts may be joined, to prolong the contact of the steam and gas
with the carbonaceous matter; and these retorts may be heated by the same or
separate fires, and the parts and proportions of the apparatus may be adjusted
and arranged according to the work to be done and to local circumstances.
The distinguishing advantages of this process, however they may be varied in
the details, are,
First, that the heated gas from the retort, and the hot air from the furnace,
are applied to generate and to heat the steam, as also to heat the water with
which the boiler is supplied.
Secondly, that the steam is introduced to the retort at the temperature at
which it is decomposable by carbonaceous substances, whereby retorts of much
larger dimensions may be used than with steam, at a lower temperature, and
used with much less liability to injury; for where the steam is introduced at a
low temperature, the heat of the furnace must be maintained much above the
decomposing point, in order to produce and keep up that degree of heat

page_text: throughout the whole mass of slowly conducting materials in the retort,
whereby there is not only a great waste of heat occasioned, but a very rapid
lestruction of the apparatus, and the addition of a water joint to the bottom of
the retort (or of any pipe cominunicating therewith), whereby the process is
carried on uninterruptedly for any length of time, and all danger of explosion
is prevented.
The third of my said improved methods consists in applying the heat
obtainable from the combustion of coal; tar, and other inflammable substances,
existing either naturally in a fluid state or capable of being reduced to that
state by heat to the generation of steam and other heating purposes. Such
liquid fuel possesses the following advantages over coal and other solid com-
bustibles, namely, that it burns away without leaving any ashes; that the
supply may be regulated with a facility and precision unattainable with coal or
other solid fuel; that it is purer, and consequently produces more heat, than
an equal weight of any solid fuel; and, lastly, that it may be easily stowed
away in tanks in the lower part of any vessel, and raised therefrom when
wanted, which renders it particularly serviceable for marine engines. The
heat produced by oils and other inflammable liquids by burning them in
lamps, has been advantageously applied to chemical purposes; and tar, resin,
and oil have also being used in conjunction with coal and coke in furnaces, but
no method has hitherto being made known of using such liquid fuel alone on a
large scale. Now, by the third of my said improved methods, such liquid fuel
may be so burnt by itself, as to be advantageously applied to the production of
steam, and to many other processes usually conducted in reverberating or other
furnaces.
A
In Figure 2 of the Drawings hereunto annexed, I have shewn how the heat
attainable from liquid fuel may be applied to the generation of steam.
represents a tubular steam boiler of the ordinary construction; B, the furnace,
which is divided into two component parts, C and D, each containing a
number of balls of baked fire clay or other incombustible substance, resting on
perforated fire bricks domes E, E. These balls may be hollow, to diminish:
the weight and increase the facility of heating them. F, an air chamber,
serving likewise as a fire-place when the furnace is to be heated; G, an open-
ing into F from the outside of the furnace; H, a blowing machine; I, a
syringe, worked by the engine for injecting the coal tar or other liquid fuel
into the furnace between the two compartiments C and D, to keep which.
syringe sufficiently cool it has an outer casing, through which a stream of
cold water is made to flow. K, flue, leading to chimney; L, chimney or
funnel; M, openings, shewn by dotted lines, in the cylinder N, for the admission

page_text: of atmospheric air; N, hot-air cylinder, communicating with L and 0; 0,
chamber, into which the hot air and vapour pass from the tubes T of the
biler, and from which they continue along the tubes P, P, to the chimney.
When the boiler is set to work, the passage G and the flue K are first
opened, and a fire made and kept up in the chamber F, till the balls in the
lower chamber have acquired a dull red heat, when some liquid fuel is slowly
injected by the syringe 1, and the blowing machine worked, whereby the whole
interior of the furnace is soon heated to a degree sufficient for the combustion
of any tar or other liquid fuel which may be injected into it. A fire in F
being now no longer necessary, G and K are closed and luted, the syringe is
supplied with fuel, and the fan wheel worked by hand or any other convenient.
nieans, to get up the steam.
After the engine has been set in motion, the fan is worked by a band
passing over a drum on the shaft. A portion of the tar or other liquid fuel
corresponding to the volume of steam required being injected at each stroke,
it is instantly and almost entirely converted into vapour, which, mixing as it is
formed with the hot air from D and Q, rises through the strata of ignited
balls in C, and becomes perfectly consumed, while any solid carbon that may
remain in D being acted upon by the current of air from F, undergoes com-
bustion (the same as charcoal would do in a coininon furnace). The flaine and
hot air resulting from the combustion pass from the furnace through the
tubes of the boiler T, T, and then through P, P, to the chimney L. For the
sake of economising the heat usually lost through the chimney, and at the
same time insuring the combustion of the fuel, the heating cylinder N is
employed, having the apertures for the admission of atmospheric air, shewn by
the dotted lines at M. The atmospheric air supplied through these apertures
passes over the tubes P, P, abstracts the heat from the hot air and vapours
which are driven through the tubes in the opposite direction, and, descending
by the chamber W, where it is further heated, is drawn through X to Y by
the action of the blowing machine, and finally propelled through the pipes Z
and Q into the furnace.
The fourth of my said improved methods consists in applying the heat obtain-
able from the combustion of coal tar and other descriptions of liquid fuel, to the
expansion of air for the production of motive power. Many plans have been
proposed for working engines by the expansion of condensed air exposed to
heat; but one great difficulty to be contended with has been to heat the air
with sufficient rapidity and regularity, and at the same time to prevent the
temperature from becoming excessive. The simpler plan is that perhaps of
passing the air through a furnace containing coal or other solid fuel, but the

page_text: ashes that are carried forward by the rapid current soon destroy the cylinder
and piston. This and other difficulties attendant on the use of solid fuel, how-
ver applied to the above purposes, are obviated by the use of liquid fuel,.
according to either of the methods shewn in Figures 3 and 4.
In Figure 3, A represents the working cylinder; B is a condensing air
pump, to be worked by the engine for supplying cold air; C, cold air pipe,
leading from the air pump to the reservoir I; D, branch pipe, from C to the-
furnace G; G, the furnace, for burning liquid fuel, as already described under
the third head of this Specification; I, reservoir of heated air, answering to.
a steam engine boiler; K, hot-air pipe; 1, throttle valve, for regulating or
cutting off the supply of hot air; M, slide valve; N, O, passages between:
the cylinder and the hot air and waste pipes; P, the passage leading to Q,
the waste air pipe; Y, chimney, for the escape of smoke and vapour when the-
furnace is to be heated. The piston in the working cylinder is represented in
the act of rising, being forced up by the hot air which passes from the reser-
voir I through the pipe K and passage 0 to the lower part of the cylinder.
In the meantime the waste air in the upper part of the cylinder which per-
formed the last stroke is escaping through the passage N, whence it passes by
the aperture P, and escapes by the pipe Q into the atmosphere. The piston
in the condensing pump is likewise in the act of rising and forcing the air from
the upper part along the pipe C to the reservoir I, a regulated portion being
allowed to proceed through the pipe E to the furnace G, from whence the pro-
ducts of combustion escape, at such a temperature that when they mix with
thic cold air from C, the whole has the temperature and expansive force
required. In order that this mixture may be perfectly effected, the heated
products from the furnace are made to pass in streams through a perforated
slab of baked fire clay A ; and, meeting with the current of air from the pipe. C
in the chamber X, the whole is made to pass in a similar manner through
holes in a
plate of cast iron B¹, into the body of the reservoir I. When
the engine is to be set to work, the throttle valve L is to be closed, the cover
of the chimney Y removed, and the furnace heated, in the manner already
described. The cover of the chimney being then firmly closed and made
air-tight, and the furnace supplied with liquid fuel, air must be forced in
by a small condensing pump to charge the reservoir with condensed air,,at
the pressure under which it is intended to work the engine, an operation
equivalent to getting up the steam in a steam engine. The piston of the
working cylinder when set to work will perforin a part of the stroke, at the
full pressure, till a quantity of hot air equivalent to the volume of cold air
injected at one stroke of the condensing pump B has passed into the

page_text: cylinder, when the supply must be cut off, and it will then act expansively, to
the end of the stroke.
Figure 4 shews a different arrangement, in which, where the same letters
occur, they refer to the same parts as in Figure 3. Here the condensed air in
the reservoir I is heated by the hot air and vapour from the furnace, passing
through the tubes S, S, in the same manner that steam is generated in a loco-
motive boiler. The condensed hot air from I passes by the pipe K and the
the passage N, O, to the working cylinder, and at each stroke of the piston a
part of the waste air which escapes by the pipe Q enters the chamber X by
branch pipes at F, F, and the remaining portion is conveyed by another
branch opening at E into the chamber G. These pipes are furnished with
registers. by which the proportion of air that passes through each may be
governed. The quantity of liquid fuel and the air for its combustion are to be
so regulated, that the mass of hot air and vapour in the chamber X shall have
the temperature required to give the expansive force desired to the air in the
reservoir I, in passing through the tubes S, S, to the chimney. This adjust-
ment having been made at the commencement of the operation, as the
supply of fuel injected by the syringe is governed by the motion of the engine,
and keeps pace with it, the same temperature, and consequently the same
expansive force in the reservoir I, will be constantly maintained without
further attention.
The fifth of my said improved methods consists in applying the heat
produced by the combustion of gaseous and liquid inflammable substances to
the warming of houses and other buildings, to roasting, and to all other pur-
poses now commonly effected by the radiant heat of an open coal fire, and in
such manner that the appearance as well as effect of a common fire may, if
desired, be produced. I fill a stove grate of any kind or a kitchen range
with pieces of fire brick or other incombustible substance or substances, and
cause jets of gas from below to play among the contents of the grate or range.
By incombustible substances, I mean such bodies as may be kept at a
red heat in contact with atmospheric air without undergoing combustion.
Thus, metals that do not oxidate under such circumstances, and metals which
are liable to oxidation, but may be protected from the atmosphere by a coating
of lute or other matter, and even charcoal so protected I consider as incom-
bustible for the purposes of my. Invention. Such incombustibles, if made hollow,
are more readily heated than when solid, and radiate as much heat. Mere
shells of fire clay or other earthy matter answer perfectly. Similar shells may be
also made of wire gauze or any thin metal, covered in the case of oxidizable
metal with any lute or vitrious matter that will protect them from the action

page_text: of the atmosphere. It is advantageous to give the back of the grate a curve
outwards, that is towards the front, as shewn in Figure 5, and the depth from
back to front may be much less than when the grate is employed for burning
coals, the quantity of heat radiated from the front at a given temperature being
in proportion to the superficial area, and not to the contents of the grate. The
front bars may be dispensed with, as the contents of the grate may be cemented
or otherwise joined and supported without them. Where the draught of the
chimney is not sufficient, any of the plans adopted with grates for coals may
be used to increase the draught, as, for instance, that shewn in Figure 5, where
the space above the grate is closed in by a plate A, leaving only a narrow
opening, B immediately above the fire. The passage above the fire should be
furnished with a damper, and the supply of air below the grate should be
regulated by a register. This is best done by closing the front of the ash
pit, and placing a register, as shewn at C, Figure 5, 6. When gas cannot be
readily obtained, I employ the vapour of inflammable liquids, which may be
generated in vessel placed above, behind, or at the side of the fire, or in any
other convenient way; or I burn such inflammable liquids in a narrow trough
or other vessel beneath the grate, which vessel may be supplied from a con-
cealed fountain on the principle of a fountain lamp. Sometimes I employ
either of the former methods to ignite the incombustible contents of the grate,
and then inject liquid fuel amongst them, as described under the third head'
of this Specification. For the purpose of injecting liquid fuel among the con-
tents of the grate, the pressure of a column of the fluid in a pipe supplied
from a reservoir above the level of the grate, regulated by a stop-cock, may be
employed. The fuel that is most readily inflamed is the best for this
such as naptha, oil of turpentine, or alcohol. Instead of filling the fire-place
of the grate in the manner above described, I sometimes remove the front
bars of the grate, and fill up the space with brick or other material. Against
this I place a plate or slab of fire brick or other substance, the size of the
front, as shewn at A, Figure 6, and in front of such plate or slab, leaving a
small space between them, I fix a sheet of wire gauze or thin plate of metal
pierced with numerous holes (B), protected, in the case of metals liable to
oxidation, in the manner above described. Between these surfaces I direct
the flame (supposed in the Drawing to issue from C), by which the gauze or
plate may be kept at a bright red heat. I sometimes make the surface of A
grooved, fluted, or corrugated, or having salient points or protuberances on the
surface to break and deflect the frame. Against such surface the flame may be
allowed to act without a second plate of metal or wire gauze,
but the quantity
purpose;
R

page_text: of radiant heat is much encreased by enclosing the flame between two surfaces,
as above described.
The sixth and last of my said improved methods relates to the application of
the light and heat resulting from the combustion of gases and vapours to
various useful purposes. It has been shewn by Sir Humphrey Davey, that
the luminous property of common flame is an effect solely owing to the intense
ignition of particles of solid carbon, and that by placing any solid incombus
tible body in flame, which is scarcely luminous, such as that of hydrogen gas,
that body on being raised to a high temperature will equally emit a powerful
light. A simple experiment will serve to illustrate these facts. If an opaque
body be held between the eye and the flame of a common candle, so as to
screen the luminous portion of it, an outer flame of a delicate blue colour will
be perceived, and if a fine platina wire be held in this flame, which is scarcely
visible, it will emit a dazzling light. The intensity of the light diminishes as
the wire is advanced farther into the flame towards the luminous portion of it,
the maximum effect being produced when it is just within the line that
separates the outer flame from the surrounding atmosphere, where the greatest
heat resides. The same effect effect is seen in what is called the Drummond
light, where an ignited jet of mixed oxygen and hydrogen gases is made to
impinge upon a ball of lime. The ignited gases, though possessing a most
intense heat, yield only a small blue flame, almost destitute of illuminating
power, but being brought in contact with a ball of lime, a most brilliant light
is produced. Here, however, the effect due to the intense heat is augmented
by the peculiar property which lime, as well as certain other earths, possess of
yielding a brighter and purer light than any other solid bodies at the same
temperature. Now, in order to increase the light obtained from substances
that are rich in carbon, and to obtain light from gases and vapours that do
not contain the proportions of carbon necessary to produce a bright flame,
I construct a cage of fine platina wire gauze or net-work of the form of the
flame, and just so much smaller than the flame, that it may be entirely
immersed in the outer portion of it, where it will soon become intensely ignited.
If the flame be conical, like that of a candle, or of any other form, having
only the outer surface in contact with the atmosphere, I use a single cage
of net-work of suitable shape in the manner above described, but in the case
of an Argand burner, I place one cylinder of wire net-work of such a size as
to be immersed in the outer part of the flame, and another similar cylinder to
the inner part. Where the flame is produced from substances rich in carbon
it is in general sufficient to make the cases or cylinders only half the height of

page_text: such flame, as it is in the lower part thereof that there is least light and most
heat, of which the flame of coal gas offers a familiar example. But although
the light emitted by platina at a high temperature is very bright, it is inferior
to that of lime and other earths at the same temperature. I therefore combine
the advantage that platina presents of forming a solid network as a substitute
for the carbon in flame, with the luminous property of lime and certain other
earths by coating the wire with such earths. When lime is used, it is not neces-
sary that it should be in a caustic.state.; the.net-work may be dipped in a mixture
of chalk and water, .and dried, and when exposed to the heat of the flame, the
carbonic acid is driven off. If quick lime be used, I prefer mixing it with oil
of turpentine, or other fluid that does not contain water. This coating not
only increases the light, but adds to the strength of the wire-work. Although
the size of the platina wire will depend on the size and intensity of the flame,
it may be taken.as.a general rule that the smaller the wire the more intense
will be the heat, and consequently the light, so that it cannot be too small,
provided the heat.of the flame be not sufficient to fuse it. The size of the
meshes or interstices will likewise vary with different flames, but the average
size may be about one twentieth of an inch. I likewise obtain a bright light
by directing a jet or jets.of.inflammable gas mixed with atmospheric air against
a ball or other shaped piece of platina, or of any other substance capable of
resisting the heat, and maintaining its form.covered with 'lime or other
earth possessing superior luminous properties. Balls .of such earths are apt
to crack or be dissipated by the heat, but as light is only radiated from
the surface of bodies.I obtain the same effect by covering other substances
which, like platina, are better calculated to resist the heat, with a thin
coating of such earths; as if the said earths constituted the whole mass of
the ball or other, shaped piece exposed to the action of the heat. Such
covering may of course be renewed as often as necessary. I sometimes sub-
stitute the vapour of inflammable liquids mixed with atmospheric air for the
above mixture of gas and air. The liquids best suited for this purpose
are oil of turpentine and naptha, as they produce an intense, heat, and may
generally be obtained at.a moderate price; but any other volatile liquid máy
be used. The vapour may be generated and the mixture made in any con-
venient manner, provided that .neither the vapour nor the air be in excess,
but the most advantageous method in practice is to pass a current of
air through such liquid. The proportions of air and vapour should be so
proportioned, that during combustion the quantity of vapour shall exactly
saturate the oxygen in the air. The quantity of vapour that a current of air
will carry with it in passing through the liquid will depend principally on its

page_text: volatility, and the temperature at which the experiment is made; but it will
likewise be influenced by the rapidity of the current of air, the size of the
bubbles into which it is divided, and the height of the column of fluid through
which it has to pass. But in practice the proper proportions are easily ensured,
without any calculation, by the following simple means :-The experiment is to
be commenced at the temperature of the atmosphere, and the liquid gradually
heated. The ignited jet of vapour and air being brought to act on the solid
that is to be employed, the intensity of the light is to be observed by the well-
known method of shadows. When it is perceived that the intensity of the light
begins to diminish, it is evident that the vapour is in excess. The temperature
is then to be noted, the liquid allowed to cool a few degrees, and the experi-
ment repeated. Two or three trials in this way are sufficient to indicate the
temperature at which the maximum effect is produced, and by maintaining
the liquid at this temperature I am enabled to ensure the proper proportions
of air and vapour for any length of time. Instead of causing the mixture of
gas or vapour with atmospheric air to impinge against the outer surface of a
ball or other shaped body, 1 sometimes employ a cage or shell of platina or
other refractory substance, pierced with numerous holes and coated with lime
or other earth, in the manner herein-before described, and cause the said
mixture of gas or vapour and air to act against the interior surface of such
cage or shell, and to pass through the holes or interstices thereof.
And having now described the nature of my said improved methods, and
the manner in which the same are to be performed, I declare that in each of
the said methods there are subordinate means made use of, which are in
themselves, separately considered, old and well known, and which I do not
therefore claim as of my Invention and protected by my Patent, otherwise
than as they are in and by the said methods newly combined and arranged, and
made subservient to new and useful purposes.
And I declare with respect to the first of my, herein-before described
improved methods, that what I particularly claim as of my Invention is, the
application of the inflammable gas resulting from the distillation of tar from
coal in aid of the said process of distillation, and the distillation of tar from a
inixture of small caking coal with small coal that does not possess the pro-
perty of caking, whether such process of distillation is effected in close vessels
or in tubes or ovens.
And as regards the second of my said improved methods, I declare that
what I claim as of my Invention, are all those peculiarities in my method of
obtaining an inflammable gas from the decomposition of water, by which
exclusively the several peculiar advantages herein-before enumerated are

page_text: obtained, but more particularly the modes of economizing the heat herein- .
before described, and the introduction of the steam into the retorts at a red
heat, or at such a temperature that it is instantly decomposible by the coke,.
charcoal, or other carbonaceous substances placed therein, and whether the gras
resulting from such decomposition of the steam is afterwards made use of by
itself or in conjunction with any other gas or vapour or other substance, for.
lighting and heating purposes.
And as regards the third of my said improved methods, I declare that what.
I particularly claim as of my Invention is, the combustion of coal tar and
other descriptions of liquid fuel, by subjecting them to a current or blast of
hot air, and also by bringing them and the vapours produced from them in
contact with incombustible bodies, heated to a state of ignition without the
employment or intervention of coal, coke, or any other description of solid
combustible.
And as regards the fourth of my said improved methods, that is to say, my
method of obtaining a motive power from the expansion of common air, I
declare that I consider the chief feature therein to consist in the employment,
according to the mode or modes herein-before described, of liquid fuel to
produce the heat requisite for such expansion, whereby the air is heated with
great celerity and uniformity.
And as regards the fifth of ny said improved methods, I wish it to be
distinctly understood, that I do not claim as of my Invention for warming
purposes,
the communication of heat by direct contact with metallic plates or
surfaces of any kind, heated by gas or by ignited gas issuing from a horizontal
or inclined surface of wire gauze or other substance, or by any other plan
whereby the radiant heat is necessarily accompanied by heated air or by the
products of combustion; but that what I particularly claim as of Invention
is, the use of incombustible substances heated to a state of ignition, in the
modes herein-before described for communicating radiant heat in the same
manner and for the same purposes that heat is radiated from the front of a
stove grate or kitchen range.
my
And as regards the sixth and last of my said improved methods, I declare
that what I particularly claim under this head is, the employment of wires of
platina or wires of any of the alloys of platina, disposed and adjusted in the
manner herein-before described, for the purpose of rendering flame luminous
or increasing its luminous properties; and that although I prefer for such
purposes the use of wires of platina or alloys of platina wrought into gauze or
net-work, I claim generally the use of pieces of platina or any of its alloys,
arranged in the form of the flame or a part thereof, whether such platina or

page_text: alloy is in the shape of wire or foil or any other shape. I claim also under
this head the method of increasing the light by coating such fabric of platina
or alloy of platina with lime or any other earth possessing superior illuminating
properties, and the use of balls or other shaped pieces of platina or other
refractory substances so covered, instead of balls or other shaped pieces formed
entirely of such earth or earths, for the production of light in the modes
herein-before described. I claim further, under the last head, the mean-
which I have herein-before described of forming a mixture of inflaminable
vapour and atmospheric air in such proportions as to obtain the maximum
of heating power from the combustion of such mixture.
In witness whereof, I, the said Alexander Cruckshanks, have hereunto
set my hand and seal, this Third day of January, One thousand eight