AN IMPROVEMENT OR IMPROVEMENTS IN THE MANUFACTURE OF GAS FOR ILLUMINA-TION
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEAN
BAPTISTE MOLLERAT, of No. 27, Leicester Square, in the County of Middlesex,
Manufacturing Chemist, send greeting.
WHEREAS His late most Excellent Majesty King William the Fourth
did, by His Letters Patent under the Great Seal of Great Britain, bearing
date at Westminster, the Second day of May, in the seventh year of His
reign, give and grant unto me, the said Jean Baptiste Mollerat, my exors,
adiñiors, and assigns, and such others as I, the said Jean Baptiste Mollerat,
my exors, adñiors, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter 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, the Invention of
"AN IMPROVEMENT OR IMPROVEMENTS IN THE MANUFACTURE OF GAS FOR ILLUMINA-
TION;" in which said Letters Patent is contained a proviso that I, the said
Jean Baptiste Mollerat, 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 His 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.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Jean Baptiste Mollerat, do hereby declare that the nature of my said Invention

page_text: is comprehended under two heads; first, the formation of the gas; second, a
process for supplying one of the carburetted matters, the employment of which
in the formation of my gas is indispensable. The gases hydrogen and oxide of
carbon not being of themselves sufficiently luminous in their combustion, it has
been suggested, as a means of encircling them with carbon, to cause them to
pass over carburetted matters, such as the oil obtained by the distillation of pit
coal (subsequently rectified), or other oils of a similar nature. In the case of
the gases hydrogen and oxide of carbon being saturated with those carburetted
matters by absorption (partension), they were capable of affording a good
luminous gas so long as they were kept at a sufficient temperature; but when,
owing to the reduction of that temperature, to their remaining too long in the
gasometers, or to their friction against the sides of the conducting tubes, the
carburetted matters were separated from the gases hydrogen and oxide of carbon,
and in consequence the remaining gases ceased to be so luminous as they were
before their union with the carburetted matters. It has also been attempted
to render the gases hydrogen and oxide of carbon more luminous by employing
burners of a peculiar form, adapted to contain carburetted matters, such as raw
oil produced by the distillation of pit coal, the same oil rectified, or other oils
of a similar nature, which oils mixing with the gases hydrogen and oxide of
carbon during their combustion rendered them more brilliant. But this
method, which is more speculative than practical, could not be brought into use
on account of the care and attention which it would have required from the
consumers, each of whom would have been obliged to keep a sufficient
quantity of carburetted matters in each burner to preserve a uniformity of
light; hence it has become necessary, to render the gases bydrogen and oxide
of carbon suitable for illumination, not only to enrich them with carbon to
render them brilliant, but also to render such richness in carbon permanent,
likewise that the distribution and consumption of the new compound should
not require extraordinary care and attention. These desiderata I have
attained, and will proceed to explain, first,-
PROCESS FOR OBTAINING MY NEW INVENTED GAS.
The new gas which I produce is not a mixture or a saturation of carburetted
matters in the gases hydrogen and oxide of carbon, the luminous properties of
which may cease from the causes I have pointed out, but it is a new combina-
tion not heretofore discovered, and absolutely permanent. This combination
takes place at the instant in which the gases hydrogen and oxide of carbon,
being raised to a high temperature, come in contact with the oils, whether

page_text: mineral, vegetable, or animal, reduced in the state of vapour or decomposed by
the action of fire; whence it results that a given quantity of oil, decom-
posed by the ordinary means would only produce one volume of luminous
gas, serves to produce three volumes of gas equally luminous. This new
combination forms a less volume than that of the gases hydrogen and
oxide of carbon on one side, and on the other side those proceeding
from the decomposition of the oil. Thus, whether hydrogen gas be pro-
duced by the decomposition of water by means of red-hot metal, or by
the action of an acid with a metal, or whether it be produced by the distilla-
tion of wood, or any other vegetable, mineral, or animal matter, or mixture of
the vapour of water with hydrogen gas, carbonic acid, or the gas oxide of
carbon, or, lastly, whether these gases be produced by the decomposition of
the water coming, either in a state of liquid or vapour, in contact with mineral,
vegetable, or animal coal in an incandescent state; these gases must be
forced to continue passing through red-hot coals, in order that the carbonic
acid may be charged with carbon, to be converted into oxide of carbon, and
in order that it may arrive afterwards with a very high temperature in contact
with any kind of oil in the state of vapour, to form at length the new gas
perfectly luminous and permanent, which is received, like other gases for
illumination, in gasometers, to be distributed for consumption. By the terms
mineral, vegetable, or animal oil or grease, I mean everything that bears the
name of oil, grease, tar, asphaltum, bitumen, petroleum, rosin, et cetera, which
may be decomposed at a high temperature, and produce combinations of carbon
and of carburetted hydrogen. My new gas for illumination does not require
washing, because it does not contain a sufficient quantity of carbonic acid to
be prejudicial to its brilliancy; neither does it contain sulphur or ammonia;
which circumstances adapt it to be burned in close rooms and against metallic
reflectors; neither does it injure colours, nor tarnish metallic bodies more
than any other natural or ordinary light; likewise, this new gas produces no
smoke, and emits but very little odour. I here give the plan of an appa-
ratus in which I really produce all the phenomena that I have pointed
out to form the new luminous gas. This apparatus will proceed to
explain with reference to the Drawings hereunto annexed; but I desire it
to be distinctly understood that I give this apparatus merely as a practical
example for the working of my Invention, and that I do not confine myself
to the employment of this apparatus in particular, but that my right extends
to every species or modification of apparatus by which analagous results
may be obtained. The apparatus I use for this purpose is delineated in

page_text: the Sheet of Drawings marked "First." Figure 1 therein shews two cylin-
ders out of the six that are exhibited in the horizontal section, Figure 3.
These cylinders are placed upright, and are heated by the elevated furnaces G,
which are so posited that the current of heated matters shall be caused
to descend through suitable flues, and envelope the external surfaces of the
cylinders prior to their being discharged into a lofty chimney. Six cylin-
ders A are placed vertically in masonry, as shown in Figure 3, and are
heated by means of two furnaces G, G, on opposite sides, for convenience;
these furnaces are provided with four doors at G, G¹, G', G. The current
of heated matters from each furnace is caused to descend, as shewn in
Figure 1, and operate upon three of the cylinders, (which constitutes one
set, two sets being fixed together for economy,) to defend which from the
violent action of the fire they are coated with semicircular bricks marked
x, x, x. The current of heated matters, after operating upon the front sides
of the cylinders, turns round at their lower ends and ascends, coming into
contact with the backs of the cylinders before it enters the middle chimneys
L, L. These cylinders may be filled with bulky combustibles, such as coke,
charcoal, or wood, and are then securely closed up. The lower ends of the
cylinders are furnished with a grating X, which is designed to prevent the
combustibles from descending into the narrow prolongation of the cylinders,
and to prevent its obstruction, which would be dangerous, as it is through this
prolongation that the gas has to pass. Three cylinders are united and worked
together at K, K. There are two annular reservoirs which surround the
middle chimneys L, L; these are respectively supplied with water by the
funnels and pipes N, N, to be reduced into vapour and afterwards conveyed
into the first cylinder of each set, as will be understood upon an examination
of the Figures 2 and 3. Oil is poured into the two funnels O, O, whence it
descends through the small tubes into a small iron vessel contained in the
third cylinder of each series, wherein it is decomposed. One of these
vessels is shewn at T, Figure 1. The vapour of water in its descent through
the ignited matter contained in the first cylinder, is decomposed; the produce
of this decomposition continues to pass by the cross tube D, then ascends
the second cylinder to pass through the incandescent combustibles, and arrives
at the upper cross tube E with high temperature, and entering the third
cylinder, it comes into contact with the vapour of the oil, by combining with
which the luminous gas is formed. In continuing to traverse the incandescent
matters contained in the third cylinder, it descends into a vertical pipe f, the
lower end of which is open, but as it is submerged in a vessel full of water, the

page_text: gas cannot escape; the oil and water only which might have been converted
into luminous gas would flow out in a liquid state.
PROCESS FOR OBTAINING ONE OF THE CARBURETTED MATTERS, THE USE OF
WHICH IN THE PREPARATION OF MY NEW GAS IS NECESSARY.
Nature produces in abundance a matter the use of which has yet been
overlooked. This matter is bituminous schistus; it exists in vast quantities
in England, and can be obtained at very little expence; this schistus
contains an oil, which is extracted by distillation; the combination of this
oil with the gases hydrogen and oxide of carbon greatly enriches the
brilliancy of the light produced by the combustion of the two latter gases.
The arrangement and construction of the apparatus which I recommend
for the distillation of the bituminous schistus is constructed after the manner
of that which I have now actually at work, and by which all the pheno-
mena or effects that I have mentioned are realized. This apparatus I
will proceed to explain with reference to the Drawings hereunto annexed;
but I desire it to be distinctly understood that I give this apparatus merely as
a practical example for the working of my Invention, and that I do not con-
fine myself to the employment of this apparatus in particular, but that my
right extends to every species or modification of apparatus by which analagous
results may be obtained. In the Sheet of Drawings marked "Second" is
represented at Figure 1 a horizontal section or plan of an apparatus, consisting
of twelve cylinders made of cast or wrought iron, which are vertically posited
in a circular arrangement, and in connection with a series of furnaces, the
flues from which, after enveloping the cylinders, proceed through lateral
apertures into a vertical chimney in the centre of the pile. These cylinders
are each marked A, and in addition respectively with the numerals 1 to 12, for
facilitating the explanation. There are three pairs of furnaces, situated at
B, C, D, each pair of furnaces consisting of one that operates on the upper
ends of the cylinders, and another, situated directly underneath, that operates
upon the lower ends of the cylinders, which arrangement is shewn in Figure 2
at B, B; only one pair of these furnaces is lighted at a time in the com-
mencement of the distillation, after which they are all three successively
brought fully or partially into operation, as herein-after explained. Bituminous
schistus, broken into small pieces, is introduced into each of the cylinders A 1
to 12, through openings or mouths at the top of each, and these cylinders,
when filled, are hermetically sealed. A tube of sheet iron, like that delineated
in Figure 6 at q, and kept in its place by three .radiating veins r, r, which

page_text: divide the cylinder into three compartments. This tube q is introduced into
the cylinders in order to force the gas or oleaginous vapours to pass through
the mass of the schistus before it disengages itself, and this passage of the gas
and vapours facilitates the operation of heating. It will be noticed that the
current of heated matters, proceeding from the pair of furnaces B, envelope in
succession ten of the cylinders (as indicated by the serpentine stream of colour
on the plan) before it is discharged into the lateral flue E, leading into the
central chimney Z. After the heat from the pair of furnaces B has then
been continued the requisite time, and the first four cylinders A. 1, 2, 3, 4,
have attained a sufficient temperature to exhaust the schistus contained in
them of its oil, these four cylinders are to be insulated from the others by
shutting a register or damper at F. The pair of furnaces C, by which the
second set of four cylinders A 5, 6, 7, 8, are heated, is now to be kindled.
The four insulated cylinders A 1, 2, 3, 4, are now to be discharged by means
of the valves or apertures at bottom; the discharging apertures being again
well closed, the cylinders are recharged with fresh schistus at the top, and are
then ready for the renewal of the distillatory process. Now the register at G
is to be opened, the effect of which will be that the current of heated matters
proceeding from the pair of furnaces C will envelope also ten cylinders (being
four more in advance), and will be discharged into the lateral flue I that
proceeds to the central chimney; next the cylinders A 5, 6, 7, 8, having
received the strongest action of the fire contained in C, and exhausted the
schistus therein, are to be insulated by shutting the register I; next the pair of
furnaces at D are to be kindled, and the last-mentioned cylinders are to be
discharged of their exhausted schistus and recharged with fresh schistus. These
being prepared for renewal of the operation, the register at F is to be opened,
by which the current of heated matters proceeding from the furnaces will
envelope ten cylinders (being four more in advance), and will be discharged
into the lateral flue J, and thence to the central chimney. The cylinder A 9,
10, 11, 12, having now received the strongest action of the fire from the
furnaces D, and exhausted the schistus of its oil, are to be in their turn
insulated by shutting the damper G; these last mentioned are, in like manner
to the foregoing, to be discharged and recharged with fresh schistus. Now the
whole twelve cylinders having been worked out and recharged, they are all
under nearly the same circumstances as when the operation commenced, and
this operation is rendered continuous by work in like manner to that described
round and round the entire circular arrangement of this distillatory apparatus.
On the top of each of the cylinders is an-aperture, having a pipe K (Figure 2),

page_text: (provided with stop-cocks) fitted thereto; through these pipes the oleaginous
and aqueous vapours, and also the hydrogen gas (which is inevitably produced),
escape by passing thence down a vertical tube L into a general conduit tube M
at bottom, that leads into a refrigeratory N, shewn in a general plan in
Figure 4; from this refrigeratory there is a tube leading into a general receiver
O, from which the oil is caused to flow into a recipient P, and the gas proceeds
from the general receiver by means of a tube Q into a gasometer R. The gas
thus collected may, if required, be applied to the purposes of illumination; but
if the gas be not so required, it may be conducted from the gasometer through
a tube S into the furnaces, where it will inflame and thereby economise the
consumption of the other fuel employed. The vertical section of the distil-
latory apparatus given in Figure 2 brings into view an elevation of two of the
cylinders, together with the flues that leading from the furnaces envelope the
sides of the cylinders, and thence proceed through lateral apertures and
channels to the chimney, as sufficiently indicated in the Drawing and by the
letters of reference, to render more literal explanation of them unnecessary.
Figure 3 exhibits an elevation of the distillatory apparatus, in which it will be
observed that it is for the most part supported upon arched vaults T, T, the
crowns of which are provided with apertures for the insertion of the lower
extremities of the cylinders, by which the emptying of the exhausted schistus,
and the opening and accurate closing of, the discharging valves or apertures,
may be easily accomplished.
The plan (Figure 4 (before alluded to), and the elevation of the same given
by Figure 5, have been sketched in the Drawing slightly, merely to assist
the reader to a ready comprehension of the general arrangement of the whole
apparatus. The several parts of the Figure 6 not heretofore explained are
not essential to the working of my apparatus, but are merely introduced to
represent some contrivances which I have found convenient; s, t, represent
an elevation and plan of a funnel for charging the cylinders with the broken
schistus, so constructed to avoid the liability of the schistus descending into
the central tube; u represents the top of the cylinder with the three apertures
closed with their covers.
Having explained the nature and details of my "improvements," I proceed to
define my exclusive claims of Invention therein, namely, I claim as of my
Invention,―
First, the new combination of liquid or ariform substances which I have
specified for producing my new luminous and permanent gas, whether produced
by the apparatus described or by any other that may be found effective for
that combination.

page_text: I claim, second, the peculiar apparatus I have described for the continuous
distillation of bituminous schistus and all imitations of the same.
In witness whereof, I, the said Jean Baptiste Mollerat, have hereunto set
my hand and seal, this Second day of November, in the year of our
Lord One thousand eight hundred and thirty-seven.
AND BE IT REMEMBERED, that on the Second day of November,
in the year of our Lord 1837, the aforesaid Jean Baptiste Mollerat came
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification 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.