IMPROVEMENTS IN THE MANUFACTURE OF BRICKS, BLOCKS, AND OTHER OBJECTS OF BLAST FURNACE SLAG
Year: 1872

page_text: LETTERS PATENT to John James Bodmer, of No. 23, The Grove,
Hammersmith, and Louis Rudolph Bodmer, of No. 2, Lansdowne
Road, Notting Hill, both in the County of Middlesex, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF BRICKS, BLOCKS,
AND OTHER OBJECTS OF BLAST FURNACE SLAG."
Sealed the 25th April 1873, and dated the 26th November 1872.
PROVISIONAL SPECIFICATION left by the said John James Bodmer
and Louis Rudolph Bodmer at the Office of the Commissioners of.
Patents, with their Petition, on the 26th November 1872.
We, JOHN JAMES BODMER, of No. 23, The Grove, Hammersmith, and
LOUIS RUDOLPH BODMER, of No. 2, Lansdowne Road, Notting Hill,. both.
in the County of Middlesex, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE MANUFACTURE OF BRICKS, BLOCKS, AND.
OTHER OBJECTS OF BLAST FURNACE SLAG," to be as follows:-
Our improvements consist in subjecting the bricks, blocks, or other
articles made of blast furnace slag with or without admixtures to heat,
and thereby burning or calcining the same.

page_text: We use blast furnace slag in a subdivided condition (subdivided by
whatever means) as admixtures; we employ fire-clay; common clay,
loam, shale, or culm, sand, chalk or other lime, fluorspar, or other
material or mixture of materials, producing in conjunction with slag the
quality most suitable for the respective purposes for which the articles
may be intended. The material is used either in a plastic or in a semi-
dry or in a dry condition, and the bricks and other articles are formed
either by hand or by machinery, and when sufficiently dry they are
calcined or burnt in any of the known ways or modes. When the
bricks, blocks, or other articles are required to be of a refractory nature,
the slag and the fire-clay and admixtures are used in the proportion
which experience will prove to give the best results; and for building
purposes, pavements, or other uses the desired degree of hardness,
density and color will regulate the admixtures.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John James Bodmer and Louis Rudolph Bodmer
in the Great Seal Patent Office on the 26th May 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
JAMES BODMER, of No. 23, The Grove, Hammersmith, and LOUIS
RUDOLPH BODMER, of No. 2, Lansdowne Road, Notting Hill, both in the
County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of November, in tho
year of our Lord One thousand eight hundred and seventy-two, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said John James Bodmer and Louis
Rudolph Bodmer, Her special licence that we, the said John James
Bodmer and Louis Rudolph Bodmer, our executors, administrators, and
assigns, or such others as we, the said John James Bodmer and Louis
Rudolph Bodmer, our 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 "IMPROVEMENTS IN THE MANUFACTURE OF BRICKS, BLOCKS, AND OTHER OBJECTS

page_text: OF BLAST FURNACE SLAG," upon the condition (amongst others) that we,
the said John James Bodmer and Louis Rudolph Bodmer, our executors
or administrators, by an instrument in writing under our, or one of our,
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
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John James Bodmer, on behalf of
myself and the said Louis Rudolph Bodmer, do hereby declare the
nature of our said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement :-
Our Invention relates to the use of blast furnace slag in bricks, blocks,
and other objects which after being pressed or moulded require calcining
or burning.
We use the slag in a subdivided or disintegrated condition in the
shape of sand or powder, and we prefer to disintegrate it by passing it
as it flows from the blast furnace direct into and through a pair of rolls
in the manner described in the Specification of Patent of John James
Bodmer, No. 1041, dated April 1866, but also use slag disintegrated by
water or by any other means.
For the purpose of more clearly defining the object of our Invention
we will divide the description of the materials used in the process into
two classes, namely, firstly, mixtures or compounds in which the slag
forms the chief substance, admixtures being used simply as binders and
fluxes, and secondly, mixtures or compounds in which the slag is used as
admixture.
In the first case when slag forms the chief substance, fluxes are used,
such as chalk and other limes, feldspar, metallic oxides, and others.
With a minimum of fluxes, the proportion of which depends chicfly
upon the nature of the slag, the slag under a low calcining temperature
is caused to cake or clinker together without fusing, and thereby prò-
duces a very light brick, which at the same time is a good non-conductor
and capable of standing a considerable degree of heat. By adding to
the slag more and more material of a more or less refractory nature,
such as common clay, culm, shale, loam, ganister, or fire-clay, and

page_text: similar substances, the bricks under a proportionately increased temper-
ature in the kiln will fuse more or less and a harder and less absorbent
brick will be produced.
In the second case when fluxes are dispensed with altogether the
object of producing refractory articles, subdivided slag is added and
mixed with the clays or other refractory material for the purpose partly
of facilitating a uniform drying of the bricks or other objects prior to
calcination, and also a more uniform and thorough calcination, and also
for improving or altering the colour and appearance of the bricks.
For the purpose of colouring oxides, calcined ore and other pigments
are used, and either mixed and amalgamated with the other materials
before they are moulded or pressed into bricks, or the ready pressed
brick before going into the kiln is dipped into or coated with the
pigment. Or the bricks after being calcined or burnt may be dipped
into or coated with pigment, or with a preparation producing an eña-
melled or glazed surface, after which the brick may again be subjected
to heat in a kiln or oven.
The slag, clay, and other materials or substances used in the manu-
facture of bricks and other objects as above named may be worked either
in a dry or semi-dry state in the shape of powder or sand or in a plastic
.condition.
Having now described the nature of our said Invention, we wish it
to be understood that what we claim as the Invention to be secured to
us by the herein-before in part recited Letters Patent is, the use of blast
furnace slag in a subdivided condition in the manufacture of bricks,
blocks, and other objects which require calcining or burning.
In witness whereof, I, the said John James Bodmer, on behalf
of myself and the said Louis Rudolph Bodmer, have hereunto
set my hand and seal, this Twenty-sixth day of May, in the
year of our Lord One thousand eight hundred and seventy-
three.