IMPROVEMENTS IN APPARATUS FOR PREPARING AND
Year: 1868

page_text: LETTERS PATENT to James Gregory, of Kingswood Iron Works, near
Bristol, in the County of Gloucester, Engineer and Ironfounder,
for the Invention of "IMPROVEMENTS IN APPARATUS FOR PREPARING AND
Sealed the 22nd December 1868, and dated the 28th September 1868.
PROVISIONAL SPECIFICATION left by the said James Gregory at the
Office of the Commissioners of Patents, with his Petition, on the
28th September 1868.
I, JAMES GREGORY, of Kingswood Iron Works, near Bristol, in the
County of Gloucester, Engineer and Ironfounder, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN APPARATUS FOR PRE-.
PARING AND COOLING ANIMAL CHARCOAL," to be as follows:-
My Invention relates to an improved construction of retort for
charring bones to produce animal charcoal and to improved apparatus
for cooling the charred products. I construct my improved retort by
inserting in a revolving heating cylinder a plate or series of plates
having longitudinal perforations made in a direction inclined to the

page_text: axis of the cylinder as described in the Specification of Letters Patent
granted to me, dated June 24th, 1868, and as a further improvement
thereon I affix to the plate or plates cross plates or pieces fixed at
certain intervals, according to the size of the cylinder. The effect of
the cross plates is to push or pass the charred substances gradually
through the retort.
My improved cooling apparatus consists of a chamber into which the
charred and heated products are received from the retort and from
which they are allowed to fall or pass through pipes enclosed in another
vessel which contains water. In cases where the requisite space can
be conveniently obtained the pipes are placed vertically in a vertical
water vessel or cistern and the charred and heated products fall by the
action of gravity through the vertical pipes or channels which are
surrounded by water. The water is introduced into the vessel or cistern
at the lower part, and is allowed to escape at the upper part, so that
the direction of the cooling currents may be opposed to that of the
descending charred and heated products. In some cases jets of water
may be made to play upon the pipes to cool their contents. In cases
where it is more convenient to place the water vessel or cistern in a
horizontal position I employ a hollow archimedean screw to convey the
charred and heated products through the horizontal cistern which is
filled by feeding currents of water applied in a direction opposite to
that in which the charred and heated products are made to pass by the
revolution of the hollow screw; I have found that by my improved
cooling apparatus I can cool down the heated charred contents of a
retort much more quickly than by the means hitherto used, I have found
in practice that when operating upon about ten hundredweight of
charred materials they may be cooled in my apparatus from a tempera-
ture of about 800° F. down to about 130° F. in an hour.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Gregory in the Great Seal Patent Office on
the 25th March 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
GREGORY, of Kingswood Iron Works, near Bristol, in the County of
Gloucester, Engineer and Ironfounder, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-eighth day of September, in the
year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said James Gregory, Her special
licence that I, the said James Gregory, my executors, administrators,
and assigns, or such others as I, the said James Gregory, 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 "Iч-
PROVEMENTS IN APPARATUS FOR PREPARING AND COOLING ANIMAL CHARCOAL,"
upon the condition (amongst others) that I, the said James Gregory,
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 imine-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Gregory, do hereby declaro
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 thereof, that is to say :-
My Invention relates to an improved construction of retort for
charring bones to produce animal charcoal and to improved apparatus for
cooling the charred products. Such retorts are arranged in pairs one
above and one below, the materials under treatment passing from the
former to the latter; I construct my improved retort by inserting in a
revolving beating cylinder a plate or series of plates having perforations
therein of a rectangular or other suitable shape made in a direction
inclined from the axis of the cylinder as described in the Provisional
Specification of an Invention for which I applied for Letters Patent on the
24th day of June 1868. The perforated plate or plates may be fixed
inside the retort by sliding them in grooves fixed to its interior or by
screwing them to suitable flanges, or may be cast with the cylinder. The
effect of employing the perforated plate or plates is to expose the sub-
stances under treatment to the influence of the heat during the
revolution of the cylinder more advantageously than has previously been

page_text: possible with non-perforated plates. I effect the object of passing the
charred substances gradually through the retort and diffusing them at
the same time more equally by using a modification of the said per-
forated plates. In this modification I make perforations in the plates of
the upper retort at the entrance end thereof, which are larger in
dimensions than those at the exit end. For ordinary retorts, say of a
length of about ten feet and of a diameter of about two feet six inches, I
use plates from one inch and a quarter to one inch and a half thick. The
sides of all the perforations both in the upper and lower retorts I make
of a bevelled shape or inclined in the direction in which the charred
products are required to travel.
to
My improved cooling apparatus consists of a chamber constructed as
shown in Figures 4 and 5 of the annexed Drawings, into which the
charred and heated products are received from the retort and from which
they are allowed to fall or pass through conducting pipes or channels
enclosed in another vessel which contains water; in cases where the
requisite space can be conveniently obtained the conducting pipes or
channels are placed vertically in a vertical water vessel or cistern and
the charred and heated products fall by the action of gravity through
the vertical pipes or channels which are surrounded by water, the water
is introduced into the vessel or cistern at the lower part and is allowed
escape at the upper part so that the direction of the cooling currents
may be opposed to that of the descending charred and heated products.
In some cases instead of the vessel or cistern being filled by an inflow of
water jets of water may be made to play inside the vessel and upon the
conducting pipes or channels so as to cool their contents in cases where
it is more convenient to place the water vessel or cistern in a horizontal
position, I employ a hollow archimedean screw to convey the charred and
heated products through pipes or channels placed in a horizontal cistern
which is filled by currents of water introduced and applied in a direction
opposite to that in which the charred and heated products are made to
pass by the revolution of the hollow screw; it is obvious that in some
cases the vessel or cistern may be used as a conducting channel for the
charred products, which may be cooled by introducing water into pipes or
channels placed inside the said vessel or cistern, the action being the
reverse of that above described.
I have found that by my improved cooling apparatus I can cool
down the heated charred contents of a retort much more quickly than
by the means hitherto used. I have found in practice that when

page_text: operating upon about 10 cwt. of charred materials they may be cooled
in my apparatus from a temperature of about 800° Fahrenheit down to
about 80 or 90° Fahrenheit in an hour.
The mode of constructing my improved retort and cooling apparatus
is more fully explained and exemplified in the Drawings hereunto
annexed where the same letters are in the various Figures used to
indicate corresponding parts.
In the annexed Drawings Figure 1 represents the perforated diaphragm
or plate as fixed inside the retort; A being the feeding end, and B the
discharging end thereof; C, C, are the perforations made in a direction
inclined from the axis of the cylinder. The dotted lines from E to F
indicate those parts of the plate which slide into the grooves in the
interior of the retort as before described.
Figure 2 is a transverse section of the cylinder with the longitudinal
plate fixed therein; and Figure 3 is an end view of the cylinder
and plate.
Figure 4 is a section of the before-mentioned vertical cistern; A is the
pipe or hopper through which the charred and heated products are con-
veyed into the chamber B; and C, C, C, C, are the pipes through which
the same descend by their own gravity, the portions of the cisterns
which contain the water are indicated by the letter D; E being the inlet,
and F the outlet.
Figure 5 is a transverse section of the cistern, the pipes being indicated
by the letter C and the water space by the letter D.
The operation of my improved apparatus is as follows:-The materials
to be charred are introduced into the retort at A, Figure 1, and as
the retort is made to revolve they are charred and passed through the
retort and caused to issue at B, whence they are conveyed by any suitable
means, as will be well understood by persons conversant with such
operations, to the pipe or hopper A in Figure 4. During the process of
cooling the charred substances are prevented from passing too rapidly
through the cooling pipes or channels by means of a moveable slide
which is placed beneath the lower ends of the pipes and by actuating
which the charred substances are retained in the pipes or allowed to
escape as may be desired. The slide is not shown in the Drawings. The
charred substances having been thus cooled are then ready for the uses
to which they are applicable.

page_text: Having now described my improvements I would have it understood
that I do not claim the parts separately which form my apparatus, but
what I claim is,―
First. The improved retort having a plate with perforations therein of
the shapes and relative dimensions as herein described.
Second. The cooling apparatus wherein the charred materials are made
to pass through pipes or channels cooled as herein described.
In witness whereof, I, the said James Gregory, have hereunto
set my hand and seal, this Twenty-third day of March, in
the year of our Lord One thousand eight hundred and sixty-
nine.
JAMES GREGORY. (L.S.)