IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE
Year: 1873

page_text: LETTERS PATENT to John Greaves Hawkins, of the Gas Works,
Sheffield, in the West Riding of Yorkshire, Gas Engineer, for the
Invention of "IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF
COMPLETE SPECIFICATION filed by the said John Greaves Hawkins
at the Office of the Commissioners of Patents, with his Petition
and Declaration, on the 22nd November 1873, pursuant to the
9th Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GREAVES HAWKINS, of the Gas Works, Sheffield, in the West Riding of
Yorkshire, Gas Engineer, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN:
APPARATUS USED IN THE MANUFACTURE OF GAS," and have petitioned Her
Majesty to grant unto me, my executors, administrators, and assigns,
Her Royal Letters Patent for the same, and have made solemn
Declaration that I am the true and first Inventor thereof.

page_text: NOW KNOW YE, that 1, the said John Greaves Hawkins, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement, reference being had to the accompanying Drawings, and to
the letters and figures marked thereon, that is to say :-
This Invention has for its object the relief of the retort from unnecessary
pressure when used in distilling coal or other gas producing material,
and ensuring a self-acting or automatic scal when the retort is not
actually engaged in the process of distillation, and is based upon an
Invention for which Letters Patent No. 220, dated January 18, 1873,
were granted to me.
The present Invention consists in making the dip pipe with a socket
and flange on the outside of the hydraulic main, and on the inside of
the hydraulic the dip pipe is increased in diameter sufficiently to admit
of the introduction of another pipe or innner ring of an annular cup,
leaving sufficient space between the two pipes for the gas to pass to the
hydraulic. This annular cup is made with the inner ring or pipe
somewhat shorter than the outer one, and is supported by a rod attached
to the bottom and extending to the top of the H pipe where the rod is
screwed, and held up by a nut which also serves to adjust the height of
the cup.
A modification of the foregoing consists in making the dip pipe larger
than it is ordinarily constructed, with an opening on one side, and a
partial division formed by bending the upper part of the dip pipe
inwards, and terminating some distance above the bottom of it, which is
closed. On the opposite side of the bottom there is an orifice into
which a screwed pipe is inserted; the top of the pipe rising to within
about half an inch more or less of the opening in the side of the dip
pipe; the object of the screw being to adjust and retain the inner pipe
to its proper height and position.
In order that the foregoing may be more easily understood Drawings
are attached hereto of which the following is a description :-Fig. 1 is
a transverse section of the hydraulic main and partial section of the dip
pipe with the annular cup, A being the hydraulic; B, the dipe;
C, C, the annular cup with inner ring or pipe D, D, and E the rod
supporting it by a bar stretched across the bottom of D.

page_text: Fig. 2 is the modification of the foregoing, before referred to, and in
which A is the hydraulic main; F, the dip partially divided by the
partition G which is a continuation of the upper part of the pipc, but
bent inwards in the manner shown; H is the pipe screwed into the
bottom of F. Fig. 3 is a front elevation and partial section of Fig. 2, and
Fig. 4 is a back elevation and partial section of the same. Similar
letters refer to the same parts in Fig. 2, 3, and-4.
The arrows indicate the direction in which the gas flows.
The action of the apparatus is as follows, and being the same as that
referred to in the Specification of the Patent before-mentioned may be
described with the exception of the letters of reference in almost
identical language:-Water being supplied to the hydraulic main to
the height shown, the pipe B, Fig. 1, or F, Fig. 2, dipping down as
depicted, and the annular cup C, Fig. 1, or dip or cup F, Fig. 2, being
full of water, the gas would upon the retort being charged and set to
work, pass down the dip pipe D, Fig. 1, or H, Fig. 2, and escape from its
bottom in the usual way; but inasmuch as the gas has a less head of
liquid to contend with if it passed through the annular cup C, Fig. 1, or
cup F, Fig. 2, it will force the liquid out of the said cups into the body.
of the hydraulic main, and maintain for itself a free passage so long as
gas is given off from the retort. The only pressure to which the retort
is subjected after the water from the cups is forced out being equal to a
head of water corresponding to the difference in level of the liquid in
the hydraulic main and the top of the pipe D, Fig. 1, or H, Fig. 2.
The moment the lid of the retort is taken off or the pressure in it ceascs
from any other cause, the water in the pipes D or H will immediately
flow into C or F, and thus effectually seal the communication between
the hydraulic main and the retort. It should however be noted that in
case the cup C or F by any unforseen occurrence becomes choked, the
gas from the retort will pass down the pipes D or H and escape from
the bottom into the hydraulic main in the ordinary manner with no
other disadvantage than that of having to contend with a deeper scal.
When the plan, as exhibited in Fig. 1 is adopted, and such an occurrence
take place, the depth of seal may be greatly reduced by lowering the
annular cup C, when the gas will escape by the pipe B through the
liquid into the hydraulic, as by the dip in common use.
The relative sizes of the various nanta.
MAT la oltored from £1.
The relative sizes of the various parts may be altered from those

page_text: shown in the illustrations which have been drawn to exhibit the
principle of the Invention rather than the exact proportions.
The advantages attendant upon the use of this improved apparatus
are a reduced pressure within the retort when at work, and consequently
an increased quantity of gas is obtained from a given quantity of coal,
while the liability to a choking of the retort by the deposit of carbon is
materially lessened if not entirely overcome. The action of the
apparatus is also automatic or self-acting and is capable of being
adjusted with ease and great precision.
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 variatons 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 my
Invention is, the construction and application of apparatus employed in
the manufacture of gas, wherein an annular cup C, Fig. 1, or pipe or
cup F, Fig. 2, are used for automatically sealing the dip pipes in the
hydraulic main, substantially as herein described.
In witness whereof, I, the said John Greaves Hawkins, have here-
unto sot my hand and scal, this Twenty-first day of November,
in the year of our Lord One thousand eight hundred and seventy-
three.