IMPROVEMENTS IN THE MEANS OF MANUFACTURING GAS
Year: 1873

page_text: LETTERS PATENT to Samuel Brothers Darwin, of Shrewsbury, in the
County of Shropshire, for the Invention of "IMPROVEMENTS IN THE
MEANS OF MANUFACTURING GAS."
Sealed the 15th July 1878, and dated the 12th March 1878.
PROVISIONAL SPECIFICATION left by the said Samuel Brothers Darwin
at the Office of the Commissioners of Patents, with his Petition,
on the 12th March 1878.
I, SAMUEL BROTHERS DARWn, of Shrewsbury, in the County of
Shropshire, do hereby declaro the nature of the said Invention for
"IMPROVEMENTS IN THE MEANS OF MANUFACTURING Gas," to be as follows:-
This Invention has for its object the utilization of common sewage by
using it as one of the ingredients from which gas for heating and
illuminating purposes may be made.
The way in which it is proposed to be used is as follows:-The sewage
having been run into tanks the liquid and the solid parts are separated
by precipitation or otherwise. The solid part is then spread upon plates

page_text: and placed on the top of the retort benches, or on the flues which may
be adapted for utilizing the waste heat issuing therefrom, where the
liquid still contained in it is soon evaporated. When the sewage is dry
it is triturated or ground in a mill, and mixed with any oleaginous sub-
stance, either liquid or solid, petroleum oil being preferred. Theso 5
ingredients may be used either by themselves or together, and in com-
bination with cinders, ashes, domestic or other refuse, such as is collected
by scavengers, or other means. When thoroughly incorporated the
material is to be thrown into retorts, carbonized in the usual way, and
subscquently condensed, purified, and distributed, either alone, or mixed 1
with ordinary coal gas or any other gas.
The residual product of carbonization may be mixed with the spent
lime used in the purification, together with a proportion of sulphate of
ammonia and other ingredients, thus constituting an artificial manure of
considerable value.
In case where gas is made by the decomposition of steam, the ash
would do admirably for insertion in the retort in lieu of coke, or the ash
after being drawn from the retorts may be used for heating foot warmers
used by railway companies.
1
The Invention is specially adapted for use where the gas manufacture 2
is in the hands of corporations or other local bodies for obvious reasons,
amongst which may be mentioned the advantages likely to arise from
the control of the sewers in the production of gas being under the same
authority, and the systems thus made to harmonize; besides, the gas-
works are usually placed at the lowest part of the town, contiguous in 2
all probability to the outfall of the sewers, which would be most con-
venient for carrying out any arrangement for the adoption of my
Invention.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Samuel Brothers Darwin in the Great Seal Patent 30
Office on the 11th September 1878.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SAMUEL
BROTHERS DARWIN, Associate of the Institution of Civil Engineers of
Shrewsbury, in the County of Shropshire, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of March, in the year
of our Lord One thousand eight hundred and seventy-three, in tho
thirty-sixth year of Her reign, did, for Herself, Her heirs and suc-
5 cessors, give and grant unto me, the said Samuel Brothers Darwin,
Her special licence that I, the sail Samuel Brothers Darwin, my
executors, administrators, and assigns, or such others as I, the said
Samuel Brothers Darwin, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time
O and at all times thereafter during the term therein expressed, should
and lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN THE MEANS OF MANU-
FACTURING GAS," upon the condition (amongst others) that I, the said
5 Samuel Brothers Darwin, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said In-
vention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
O months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Samuel Brothers Darwin, do hereby
declare the nature of my said Invention, and in what manner tho
same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the accom,
panying Drawing, and to the letters marked thereon, that is to say:- ·
This Invention has for its object the utilization of common sewage, by
using it as one of the ingredients from which gas for heating and
illuminating purposes may be made.
The way in which it is proposed to be used is as follows:-The sewage
having been run into tanks, the liquid and the solid parts are separated
by precipitation or otherwise. The solid part is then taken out, deodo-
rized, and spread upon plates, tiles, or other suitable surface, and placed
on the top of the retort benches, and on tho flues which may be so
arranged as to adapt them for thus utilizing what may now be considered,
and would otherwise bo waste heat. The liquid still contained in the

page_text: sewage is here soon evaporated. When the sewage is dry it is triturated
or ground in a mill, and mixed with any oleaginous substance, either
liquid or solid, petroleum oil and coal tar being preferred. These
ingredients may be used either by themselves or together, and in com-
bination with cinders, ashes, bones, putrid flesh or fish, domestic or 5
other refuse such as is collected by scavengers or other means. When
thoroughly incorporated by machinery or other means the material is to
be thrown into retorts, carbonized in the usual way, and subsequently
condensed, purified, and distributed either alone or mixed with ordinary
coal gas or any other gas.
The residual product of carbonization may be mixed and ground by
machinery with the spent lime used in the purification, together with a
proportion of sulphate of ammonia and other ingredients, thus con-
stituting an artificial manure of considerable value.
In case where gas is made by the decomposition of steam, the ash 1
would be admirably adapted for insertion in the retort in lieu of coke, or
the ash after being drawn from the retorts may be used for heating foot
warmers used by railway.companies, or, when cool, sampled for filtering
and other purposes.
10
Although no special form of apparatus is requisite for carrying out 20
this Invention, it is highly important that the greatest economy should
bo studied, and as the reduction of the seal in the hydraulic main is
conducive thereto, by relieving the retort from undue pressure and
ensuring a greater yield of gas from a given quantity of material, I have
been induced to devise means for this purpose, and have secured the 21
rights thereto by Letters Patent No. 90, dated January 13, 1871, and
No. 1382, dated May 28, 1871.
In addition to the plans there exhibited I have invented improvements

page_text: •
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or float upon the surface of the liquid contained therein. The top of
the cap is furnished with a rod or spindle which works through a holo in
a guido bar attached to the hydraulio, or the spindle may pass through
the cap, one end working through a guide bar fixed to the hydraulic, and
the other to a similar guide bar stretched across the top of the ascension
pipe. By these means the cap or cover is maintained in proper position
the cap, one end working through a guide bar fixed to the hydraulic, and
the other to a similar guide bar stretched across the top of the ascension
pipe. By these means the cap or cover is maintained in proper position
for effective duty.
°
In order that the arrangement of the cap may be more easily under-
stood a Drawing in sectional elevation is attached hereto, of which the
) following is a description :-
A is the hydraulic main; B, the ascension pipo; and O, the cap with
its guide rod D, D, and guide bars E, E; Fbeing the float.
The result of using this kind of apparatus is that when the retort is
in action the gas has to contend with scarcely any dip or scal on entering
the hydraulic main, but escapes under the edge of the floating cap and
is conveyed away in the usual course; but when the retort is discharged
or out of action, the back pressure forces the liquid under the cap
between it and the enclosed ascension pipo, thus forming an effective
seal against the return of any gas.
The Invention is specially adapted for use where the gas manufacturo
is in the hands of corporation's or other local bodies having charge of the
sanitary matters, for obvious reasons, amongst which may be mentioned
the advantages likely to arise from the control of the sowers, the gathoring
of ashes and other refuse by the scavengers (admixed as it often is with
5 coal slack and other gas yielding substances, and the production of
gas being under the same authority; besides the gas works are usually
placed at the lowest part of the town, contiguous in all probability to
the outfall of the sewers, which would be most convenient for carrying
out any arrangement for the adoption of my Invention, the result being
the prevention of contaminated rivers and streams.
Having now described and particularly set forth the nature of this
Invention, and the manner in which the same is or may be used or
carried into effect, I wish it to be understood that I do not confine or
restrict myself to the precise details which I have described or referred
3 to, as variations may be made therefrom without deviating from the

page_text: principles or main features of this Invention; but what I consider to be
novel and original, and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is, the manu-
facture of gas substantially as herein described.
In witness whereof, I, the said Samuel Brothers Darwin, have here- 6
unto set my hand and seal, this Tenth day of September, in the
year of our Lord One thousand eight hundred and seventy-
three
SAMUEL BROTHERS DARWIN. (L.S.)
Witness to the signaturo of
the said Samuel Brothers
Darwin,
JAS. G. SPENCE,
Iron & Coal Merchant,
Shrowsbury.