IMPROVEMENTS IN APPA- RATUS USED IN THE MANUFACTURE OF GAS
Year: 1871

page_text: LETTERS PATENT to Samuel Brothers Darwin, of Shrewsbury, in the
County of Shropshire, for the Invention of "IMPROVEMENTS IN APPA-
RATUS USED IN THE MANUFACTURE OF GAS."
Sealed the 17th November 1871, and dated the 23rd May 1871.
PROVISIONAL SPECIFICATION left by the said Samuel Brothers Darwin
at the Office of the Commissioners of Patents, with his Petition,
on the 23rd May 1871.
I, SAMUEL BROTHERS DARWIN, of Shrewsbury, in the County of
Shropshire, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF GAS," to be as
follows:-
The object of this Invention is to prevent the choking of the ascension
pipes leading from the retorts to the hydraulic main, to afford a ready
means for cleaning them out should they be accidentally stopped, and to
relieve the retorts from irregular or undue pressure during the process
of distillation.

page_text: For these purposes the ascension pipe instead of terminating in a H
and dip pipe is attached to or enters through and rises some distance
above the bottom of the hydraulic main, which may be fitted in either of
the two following ways:—
Firstly. By placing over and around the ascension pipe within the
hydraulic a short dip pipe. This dip pipe is of larger diameter than the
ascension pipe and reaches from the top of the hydraulic where it is
fastened to some distance below the top edge of the ascension pipe.
Secondly. By constructing the hydraulic main with two longitudinal
division plates, one plate, which may be called the rising plate, being
fastened to the bottom and reaching to within a few inches of the top,
while the other division plate, which may be called the dip plate, is
fastened to the top and extends downwards to within a few inches
of the bottom. The hydraulic is thus divided longitudinally into two
compartments, the space between the two division plates serving as a
channel of communication from one to the other. Between the orifices
in the bottom of the hydraulic where the ascension pipes enter, trans-
verse division plates are fastened extending from top to bottom, and
from one side of the hydraulic main to the dip plate. In the top of
the hydraulic main and directly over the entrance of the ascension pipes
(in whichever of the two preceding arrangements of hydraulic main is
adopted) orifices are made of sufficient size to allow of suitable instru-
ments being readily introduced for the purpose of clearing the ascension
pipe if it should become necessary. When the retorts are in action
these orifices are closed by a suitable lid, plate, or plug. Water or other
liquid is admitted in such quantity as to form a seal between the two
longitudinal compartments of the hydraulic main or between the dip
and ascension pipes. The gas formed in the retort passes up the
ascension pipe and under the edge of the dip pipe into the upper part
of the hydraulic, in the first arrangement of the latter, and thence to
a gas holder, and in the second arrangement the gas passes up the
ascension pipe into the front compartment of the hydraulic over the
rising plate, and beneath the dip plate into the back longitudinal com-
partment of the hydraulic, and from thence to a counterbalanced gas
holder, which is used for the purpose of reducing the pressure on the
retorts to a minimum, the exhauster being employed in these arrange-
ments to draw the gas from the holder and force it through the different
apparatus necessary for its complete manufacture.

page_text: By these means the liability to produce a vacuum in the hydraulic and
the probability of making bad gas in consequence is greatly decreased,
while the facilities offered for clearing the ascension pipes constitute a
great improvement upon the present system.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Samuel Brothers Darwin in the Great Seal Patent
Office on the 20th November 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SAMUEL
BROTHERS DARWIN, of Shrewsbury, in the County of Shropshire, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of May, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Samuel Brothers Darwin, Her special
licence that I, the said Samuel Brothers Darwin, my executors, admi-
nistrators, 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 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 "Ix-
PROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF GAS," upon the
condition (amongst others) that I, the said Samuel Brothers Darwin,
my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, 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 months next and imme-
diately 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 the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying.

page_text: Drawings and to the letters and figures marked thereon, that is to
say :-
The object of this Invention is to prevent the choking of the ascension
pipes leading from the retorts to the hydraulic main, to afford a ready
means for cleaning them out should they be accidentally stopped, and
to relieve the retorts from irregular or undue pressure during the
process of distillation.
For these purposes the ascension pipe A (in Fig. 1, which is a
transverse sectional elevation of the arrangement) instead of terminating
in a H and dip pipe, is attached to or enters through and rises some
distance above the bottom of the hydraulic main B, which may be fitted
in either of the two following ways:—
Firstly. By placing over and around the ascension pipe A within the
hydraulic a short dip pipe C. This dip pipe is of a larger diameter than
the ascension pipe, and reaches from the top of the hydraulic, where
it is fastened to some distance below the top edge of the ascension
pipe.
Secondly. By constructing the hydraulic main (as shown in Fig. 2,
which is a sectional plan throug Y, Z, of Fig. 3, the latter being a
transverse sectional elevation of the same) with two longitudinal division
plates, one plate D, which may be called the rising plate, being fastened
to the bottom and reaching to within a few inches of the top, while the
other division plate E, which may be called the dip plate, is fastened to
the top and extends downwards to within a few inches of the bottom.
The hydraulic is thus divided longitudinally into two compartments F
and G, the space H between the two division plates serving as a channel
of communication from one to the other. Between the orifices in the
bottom of the hydraulic where the ascension pipes enter transverse
division plates I, Fig. 2, are fastened, extending from top to bottom,
and from one side of the hydraulic main to the dip plate E. In
the top of the hydraulic main and directly over the entrance of the
ascension pipes (in whichever of the two preceding arrangements
is adopted) orifices are made of sufficient size to allow of suitable
instruments being readily introduced for the purpose of clearing the
ascension if it should become necessary. When the retorts are in action
these orifices are closed by suitable lids, plates, or plugs J. Water or
other liquid is admitted in such quantity as to form a seal between
the two longitudinal compartments of the hydraulic main, or between.

page_text: the dip and ascension pipes. Over each ascension pipe attached to the
hydraulic main and passing through the lid or plate J, or through
the top of the hydraulic main or through the side thereof, is a small
pipe K fitted with a stop-cock and supplied with water. This pipe
serves to convey a small stream of water into the ascension pipe, thereby
keeping it cool and greatly assisting in maintaining it free from
obstruction. I make no claim however to this method of introducing
the water. The gas formed in the retort passes up the ascension pipe
and under the edge of the dip pipe into the upper part of the hydraulic
in the first arrangement of the said hydraulic, and thence to a counter-
balanced gas holder; and in the second arrangement the gas passes up
the ascension pipe into the front compartment of the hydraulic over the
rising plate, and beneath the dip plate into the back longitudinal com-
partment of the hydraulic, and from thence to a counterbalanced gas
holder which is used for the purpose of reducing the pressure on the
retorts to a minimum, the exhauster being employed in both these
arrangements to draw the gas from the holder, and force it through
the different apparatus necessary for its complete manufacture. Any
ordinary counterbalanced gas holder and exhauster will answer the
purpose, it is therefore unnecessary to illustrate them in the accom-
panying Drawings.
By these means the liability to produce a vacuum in the hydraulic
and the probability of making bad gas in consequence is greatly
diminished, while the facilities offered for clearing the ascension pipes
constitute a great improvement upon the present system.
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 would observe in conclusion that I do not confine
or restrict myself to the precise details or arrangements which I have
described or referred to, as variations may be made therefrom without
deviating from the 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,―
Firstly. The arrangement of a short dip pipe, as shown in Fig. 1.

page_text: And, thirdly. The interposition of a counterbalanced gas holder
between the hydraulic main and the exhauster, substantially as herein
described.
In witness whereof, I, the said Samuel Brothers Darwin, have
hereunto set my hand and seal, this Eighteenth day of November,
in the year of our Lord One thousand eight hundred and seventy-
one.
SAMUEL BROTHERS DARWIN. (L.S.)