IMPROVEMENTS IN THE MANUFACTURE OF GAS FOR ILLUMI- NATION, AND OF THE RESIDUAL PRODUCTS INTO ARTICLES OF COMMERCE
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
CLINTON ROBERTSON, of 166, Fleet Street, in the City of London, Civil
Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Sixth day of July,
One thousand eight hundred and forty-eight, in the twelfth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Joseph Clinton Robertson, my exors, adiñiors, and assigns,. Her
especial licence, full power, sole privilege and authority, that I, the said
Joseph Clinton Robertson, my exors, adññors, and assigns, or such others as
I, the said Joseph Clinton Robertson, my exors, admors, 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, Wales, and the Town of Berwick-
upon-Tweed, in the Islands of Guernsey, Jersey, Alderney, Sark, and
Man, and also in all Her said Majesty's Colonies and Plantations abroad,
the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF GAS FOR ILLUMI-
NATION, AND OF THE RESIDUAL PRODUCTS INTO ARTICLES OF COMMERCE," commu-
nicated to me from abroad; in which said Letters Patent is contained a

page_text: proviso, that I, the said Joseph Clinton Robertson, should cause a particular
description of the nature of the said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal, to
be inrolled in Her 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
Joseph Clinton Robertson, hereby declare that the nature of the said Invention,
and in what manner the same is to be performed, are, according as they
have been communicated to me, fully described in and by the present Speci-
fication thereof, that is to say:-
Firstly, the gas for illumination is manufactured in manner following from
rosin, in conjunction or combination with potash and lime, or soda and lime,
or potash, lime, and soda, or any one or two of the said substances in combi-
nation with any other alkaline substances, one, two, or more, and in conjunc-
tion also with sawdust, or any other fibrous vegetable matter in a fine com-
minuted state. These crude materials are mixed together (in proportions for
which no specific rules are given, as almost any combination of them is pro-
ductive of a beneficial result), and placed in moveable cast-iron cases of a
cylindrical or any other form adapted to the shape of the retort in which their
distillation is to be afterwards effected, which cases are permanently closed
at one end, and have at the other end caps, covers, or plugs, which are fitted
to them so loosely as to be easily driven off by a little internal pressure.
These cases are placed in a retort precisely similar to an ordinary gas retort,
and set like it in brickwork, and they are so arranged as to leave room for
the escape of the caps, covers, or plugs when driven off as aforesaid. This
retort being heated in the usual way, the resulting volatile or gaseous pro-
ducts are conveyed by a tube into a second retort of the same description as
the first, filled, or nearly so, with lumps of coke, or lime, or broken brick, or
other like materials in a fragmental state (in order that they may present &
large decomposing surface), and heated to a cherry redness previously to the
introduction of the gaseous products. If only a very pure gas for purposes of
illumipation is desired to be obtained, the gas which escapes from the second
retort is made to travel through a third or fourth retort filled with materials
of the same description, and in the same incandescent state as thoso used in
the second.
But,
Secondly, when it is desired to separate and collect the oil or oleaginous

page_text: matters held in suspension by the gaseous products resulting from the dis-
tillation in the first retort, these gaseous products are passed through a close
tank nearly filled with water, and fitted with an ascension pipe which leads
to a hydraulic main, such as is in ordinary use in gas manufactories. The
water retains the oil or oleaginous matters, or at least the larger portion
thereof, while the gas which passes off to the hydraulic main is conveyed
thence to a water washer passed next through a dry line or milk of lime
chamber, and finally delivered to a gasholder.
Thirdly, from the oil obtained in manner aforesaid, an antifriction grease
of a superior quality is made by mixing it with milk of lime or dry lime, and
adding a quantity of zinc, or some, one or other of the alloys of zinc reduced to
a granulated state, in the proportion of about five parts of zinc or alloy of
zinc to each hundred parts (by weight) of the oil.
Fourthly, from the same oil there is obtained a spirit, which may be used
both for illumination and as a varnish or vehicle for color, by distillation and
rectification. In first distilling the oil, care is taken not to raise the tempe-
rature higher than is just sufficient to give the oil, which is originally of a
yellowish color, a brownish, or tawny appearance. The spirit which comes
over from this first distillation is afterwards rectified by redistilling it once,
twice, or oftener, in combination with a small quantity of lime in each
instance, until it attains any required degree of whiteness. The proportion of
lime to spirit which is found to answer best in practice is about three quarters
of an ounce of the former to each pound weight of the latter.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that the improvements claimed
under this Patent are as follows:-
First, the manufacture of gas for illumination from rosin, by mixing it with
alkaline and vegetable fibrous substances, and exposing these crude materials
to the action of heat in cases placed in retorts, and passing the resulting
volatile or gaseous products through retorts, one, two, or more, filled with
lumps of coke, or lime, or broken brick, or other like materials, in a fragmental
and incandescent state, as before described.
Second, the separation and collection of the oil or oleaginous matters con-
tained in the volatile or gaseous products resulting from the first distillation
of the said crude materials, by passing the same through water, as before
described.
Third, the manufacture from the said oil of an antifriction grease, by the
admixture of lime and zinc, or some alloy of zinc, as before described.

page_text: Fourth, the manufacture from the said oil of a spirit, by the process and
the means before described.
In witness whereof, I, the said Joseph Clinton Robertson, havo hereunto
set my hand and seal, this Sixth day of January, One thousand eight
hundred and forty-nine.
J. CLINTON (L.s.) ROBERTSON.
Enrolled the Sixth day of January, in the year of our Lord One thousand
eight hundred and forty-nine.