Ax IMPROVE- MENT IN THE CONSTRUCTION OF CLAMPS FOR BURNING BAW, BRICKS
Year: 1824

page_text: RHODES SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
RHODES, of Baulms, Hoxton, in the Parish of Hackney, in the County of
Middlesex, Brickmaker, send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twentieth day of November, in the fifth year of His reign,
did, for Himself, His heirs and successors, give and grant unto me, the said
William Rhodes, His especial licence that I, the said William Rhodes, my
exors, admors, and assigns, or such others as I, the said William Rhodes,
my exors, admors, and 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, my Invention of "Ax IMPROVE-
MENT IN THE CONSTRUCTION OF CLAMPS FOR BURNING BAW, BRICKS;" in which said
Letters Patent there is contained a proviso obliging me, the said William
Rhodes, by an instrument in writing under my hand and seal, particularly to
describe and ascertain the nature of my said Invention, and in what manner
the same is to be performed, and to cause the same to be inrolled in His
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
annear).

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Rhodes, do hereby declare that my said Invention, and the manner in
which it is to be produced and carried into effect, is herein-after particularly
set forth and described (that is to say) :-
Its object is to produce a greater quantity of good, sound, and saleable
bricks out of the same clamp or kiln, and with nearly the same quantity of fuel
as heretofore used, whereby a considerable saving will accrue to the brick-
maker. And in order the better to explain how this is effected, and what my
views are upon the subject, it will be necessary to describe briefly the manner
in which brick clamps or kilns have been heretofore topped or finished, and
the effects which I believe to occur in the burning of bricks in them. It must
be understood that what I am saying applies to such clamps or brick kilns as
are formed and constructed in the open air, without any building or erection
to protect them from the weather, according to the London practice of brick-
burning, though my aforesaid Invention herein-after described applies equally
to the burning of bricks in that manner, or in close or other kilns. The usual
construction of a clamp of bricks is to leave air or draught holes at or near
the bottom among the first few courses of which the main or principal body of
fuel is deposited, after which the raw bricks are set or piled closely by the
side of each other, with a very small quantity of breeze or other fuel strewed
among them; and in this way the clamp is carried up to nearly its intended
height, when it is stopped or finished by placing or tasking two courses of place
or other inferior burnt bricks on edge, but close to each other, over the whole
top of the kiln, which two courses are, in the technical language of brick
burning, called cantlings, and again covering these by one or two other courses
of similar burnt bricks laid flatways, and close to each other, which last
or finishing course or courses are called plattings. The number of topping or
finishing courses of cantlings and plattings is increased or diminished at times
according to the skill and judgment of the brickmaker and the nature of the
season in which he is about to burn the clamp or kiln, but the bricks forming
them are always laid close together, and with the joints broken or not over
each other, their use being to prevent any rain that may fall upon the clamp
or kiln from getting into and penetrating the same, and thereby softening
the upper courses of raw bricks, which, although dried upon the hacks,
are nevertheless soluble from not having yet been burnt, and which, if
rendered moist, would never harden in the fire, but would turn out soft and
friable, or what is technically called shuffy, and therefore unfit for the purposes
of building. Place, or soft and absorbent bricks, are commonly selected for
the cantlings and plattings, in order that they may more effectually absorb

page_text: and stop the progress of any rain falling on the clamp or kiln, which
would not only produce the effect above described, but also tend to check
the heat and progress of the fire, notwithstanding the above precaution and
process in covering the clamp or kiln, which does very effectually keep out
all wet, but still it very commonly occurs in practise that the three or four
upper or last courses of raw bricks turn out shuffy and of bad quality, if not
unfit for use, to the great loss and detriment to the brickmaker; and this,
particularly in wet seasons, has been attributed to the insufficiency of the
covering of cantlings and plattings, although increasing them has not been
found to remove the inconvenience. It occurred to me that as the main body
of fire was at the bottom of the clamp or kiln where the heat first commences,
and as the whole body of such clamp or kiln is composed chiefly of raw bricks,
which, although dried to a considerable extent upon the hacks in the open air
and sun, yet must contain much wet or moisture, particularly in the middle of
the brick, that great quantities of steam or aqueous vapour would arise and
ascend in the clamp or kiln upon the first application of the fire, which vapour
would naturally condense upon the raw bricks in the upper part of the clamp,
which would be yet cold from not having felt the effects of the fire, while the
formation of the cantling and platting courses made close to exclude external
wet would in like manner prevent the escape of the steam, and would thus
bring about the very effect they were intended to prevent. With a view,
therefore, to remove this difficulty and inconvenience so long felt and com-
plained of, I form and construct the covering of my clamps and kilns in the
following new and improved manner, which new mode of construction is my
Invention, and the subject of which I claim the sole and exclusive benefit and
advantage under my aforesaid Patent; (that is to say,) the clamp or kiln is
set or put up, and fuel applied to it in the usual and accustomed manner,
until it arrives at the height of within one or two courses of where the lowest
scantling course would be placed; but instead of so placing it, I skintle one or
two of the last courses of raw bricks, (that is to say,) I place them with an
opening of at least half an inch between one and another, and dispose them
rather diagonally, filling up the intervals so formed with small coke or breeze.
The cantling course then comes on, of which I use but one; and instead of
placing all the burnt bricks which form it close together, I leave spaces or
openings in the manner of what is technically called pigeon-holeing over the
whole top or surface of the neck of raw bricks, such tunnels or pigeon-holes
running the whole-length of the clamp or kiln; and I then finish,-as-usual,
with either two or three courses of plattings. And lastly, if the season is late,
or appears likely to be wet, I finish the clamp by spreading over its top, above

page_text: the platting courses, about three or four inches of brick rubbish or soil. In
the lowest platting course I form other pigeon-holes or tunnels, which run
directly across the kiln or at right angles to those formed below in the cantling
course with which they communicate; and these last-mentioned pigcon-holes
or tunnels are made at about every ten or fifteen fect asunder, and run over
the clamp or kiln to the distance of about one third over its top from each
side, and I cause those tunnels or pigeon-holes which occur in the central
part of the kiln to be so placed as not to be quite opposite to them, or I make
them open at the ends of the clamp or kiln; but this form and disposition, as
well as the number of upper tunnels, may be varied, since all that I require is,
that they shall admit of sufficient vent for all the steam and damp of the kiln,
which will be easily determined by experience.
From the above description it will appear that the benefit to be derived
from my aforesaid Invention consists in obtaining a more perfect and imper-
vious covering for the clamp or kiln in wet seasons by the use of brick rubbish
or soil, while there is at all times a free and open vent and escape for any
steam or vapour that may arise in the body of the clamp or kiln, by means of
the skintling of the one or two last courses of raw bricks, and the tunnels or
pigeon-holes left or formed in the top of it as aforesaid; and I find the effect
of this to be, that very few (if any) shuffy bricks are found in the clamp or
kiln so constructed, and this it is the object of my Invention to prevent.
In witness whercof, I, the said William Rhodes, have hereunto set my
hand and seal, this Twentieth day of May, in the year of our Lord
One thousand eight hundred and twenty-five.
WILLIAM (L.s.) RHODES.
AND BE IT REMEMBERED, that on the Twentieth day of May, in the
year of our Lord One thousand eight hundred and twenty-five, the aforesaid
William Rhodes came before our said Lord the King in His Chancery, and
acknowledged the Specification aforesaid, and all and every thing therein
contained and specified, in form above written. And also the Specification
aforesaid was stamped according to the tenor of the Statute made for that
purpose.
Inrolled the Twentieth day of May, in the year of our Lord One thousand