IMPROVEMENTS IN THE MANUFACTURE OF BRICKS, BLOCKS, TILES, OR OTHER LIKE ARTICLES CAPABLE OF BEING EMPLOYED FOR BUILDING OR OTHER PURPOSES
Year: 1872

page_text: LETTERS PATENT to Carl Friedrich Claus, of Middlesborough, in the
County of York, Chemist, for the Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF BRICKS, BLOCKS, TILES, OR OTHER LIKE ARTICLES
CAPABLE OF BEING EMPLOYED FOR BUILDING OR OTHER PURPOSES."
Sealed the 14th March 1873, and dated the 11th December 1872.
PROVISIONAL SPECIFICATION left by the said Carl Friedrich Claus at
the Office of the Commissioners of Patents, with his Petition, on
the 11th December 1872.
I, CARL FRIEDRICH CLAUS, of Middlesborough, in the County of
York, Chemist, do hereby declare the nature of my said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF BRICKS, BLOCKS, TILES, OR OTHER LIKE
ARTICLES CAPABLE OF BEING EMPLOYED FOR BUILDING OR OTHER PURPOSES," to be as
follows:-
This Invention relates to the production of bricks, blocks, tiles or
> other like articles capable of being employed for building or other

page_text: purposes, and consists in the employment of what is known as blast
furnace slag in a state of division either alone or in conjunction with
clay, also in a fine state of division, and also by preference of a refractory
character.
In carrying out my Invention I employ finely ground blast furnace
slag as the chief constituent of the mass or material from which I
manufacture flooring and other tiles, bricks, blocks, and other like articles
capable of being employed for building and other purposes, either plain
or ornamental, and I mix with the same variable but small quantities of
clay as a binding material.
According to the intended mode of subsequent mechanical treatment,
videlicet, of moulding it into the articles named, I moisten this mixture
with more or less water, that is to say, if the process known as dry
pressing is to be employed I use such a quantity of water which is
known to be suitable for that purpose, whilst if the mass is to be roughly
moulded first, then partly dried, and afterwards pressed, a larger quantity
of water is added. The exact degree of plasticity required for moulding
the material will assist the manufacturer in finding out the proper
quantities of water to be used. Eight to ten per cent. of water will
produce the requisite condition for the process of dry pressing.
The degree of fineness to which the slag has to be pulverized depends
upon the nature of the articles to be made, and the proportion of clay to
be employed to that of pulverised slag depends partly on the fineness of
the powdered slag and partly on the character of the article to be made;
thus the finer the slag is powdered the less the quantity of clay which
.is required to bind the mass together; and further, the smaller the
quantity of clay employed the more flinty or glassy will be the nature
of the article manufactured.
Although in most cases I prefer to use a small quantity of clay in the
preparation of the mass it is quite possible to use pulverized slag alone if
it is fine enough, so as to give the moistened mass sufficient plasticity.
The mode of making the articles enumerated is the same as that
followed with regard to ordinary clay ware, that is to say, they are either
dry pressed, as stated already, or roughly moulded and then pressed.
After having been pressed they are either air or stove dried in the usual

page_text: way and then burned in brick or other kilns of the usual construction,
in which the products of combustion come into contact with the articles
to be burned. But it is important that the construction of the kiln is
such that a uniform distribution of heat can be effected throughout.
Another precaution is necessary to be observed which is not required in
the manufacture of ordinary clay ware, but upon the observance of
which depends the success of the manufacture of this new class of
goods, which is, that in packing the kiln the tiles or other goods are so
placed that they do not more frequently than is necessary touch one
another. By neglecting this precaution utter failure of producing an
useable article would be the result. It has further to be observed in the
burning of these goods that the larger the proportion of powdered slag
is to that of clay the more has the firing in the kiln to be conducted with
caution and the heat to be kept proportionally lower..
For the proportions instanced below about a light red heat should
be employed in the burning.
The kind of clay which is best suited for this manufacture is that which
approaches in character a refractory clay.
The proportion of powdered slag and clay may, as has been stated, be
varied according to the nature of the goods to be produced.
An exceedingly hard brick, tile, building, or other materials can be
produced, for instance, by a mixture of from 90 to 70 parts by weight
of pulverised slag to from 10 to 30 parts of clay, but other proportions
will give good results.
5 SPECIFICATION in pursuance of the conditions of the Letters Patent,
•
filed by the said Carl Friedrich Claus in the Great Seal Patent
Office on the 7th June 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CARL
FRIEDRICH CLAUS, of Middlesborough, in the County of York, Chemist,
0 cand creating

page_text: 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 suc-
cessors, give and grant unto me, the said Carl Friedrich Claus, Her
special licence that I, the said Carl Friedrich Claus, my executors,
administrators, and assigns, or such others as I, the said Carl Friedrich
Claus, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times there-
after 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 Inven-
tion for "IMPROVEMENTS IN THE MANUFACTURE OF BRICKS, BLOCKS, TILES, OR
OTHER LIKE ARTICLES CAPABLE OF BEING EMPLOYED FOR BUILDING OR OTHER
PURPOSES," upon the condition (amongst others) that I, the said Carl
Friedrich Claus, 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 immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Carl Friedrich Claus, 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 :—
My Invention relates to the manufacture of bricks, blocks, tiles, and
slabs, and similar articles capable of being used for building and other
purposes, and consists in the application of blast furnace slag in a state
of fine division either alone but in preference in combination with clay
in a state of fine division and of such a character which approaches that
of refractory clay.
In carrying out my Invention I use more or less finely ground blast
furnace slag as the basis and main constituent of the mass or material
from which I manufacture the ceramic articles enumerated above, and I
mix therewith variable but small quantities of clay as a binding
material.
I am aware that ground blast furnace slag has been proposed by others
11

page_text: of about 5 as a flux, but in my process I employ the same as the main
constituent of the mass, together with clay, and I obtain thereby a
manufactured article of a widely different character to that obtained by
the hitherto known methods.
The blast furnace slag may be ground or disintegrated by any of the
known methods, but if it is to be used alone or with only a small
quantity, say 10 f of clay, that kind of slag is preferred which has been
obtained by running the liquid hot slag into water, and grinding the
product. For a larger proportion of clay the powder obtained from the
cold hard slack may be used.
The degree of fineness to which the slag has to be ground and sifted
depends upon the character and size of the article to be made. In a like
manner the proportion of powdered slag and clay is dependent from the
character of the article to be made, the nature of the clay to be used,
and the degree of fineness to which the slag is pulverized. As these
conditions are exceedingly variable it is impossible to give the necessary
description of process applicable for all cases; but if the clay used is of
a somewhat refractory character a proportion of 20% to 25% of clay will
give a material applicable for general purposes, the powdered slag being
at the same time of the degree of fineness which is got by passing it
through a No. 20 or 25 sieve. According to the character of goods
to be made, and the nature of the materials in hand, I vary the pro-
portion of slag from forty to ninety per cent. of the mass, the remainder
being the slag.
Non refractory clays I use also, but it requires a little more of the
same than of the former.
It was stated above that the clay to be admixed to the powdered slag
is also used in a state of fine division, and this fine state of division I
obtain by drying the clay, pulverizing and sifting the same, or by mixing
a large quantity of water with the same, that is, by converting it into a
fine liquid sludge or mud.
The powdered slag and finely divided clay I now mix together by any
known mixing appliance in the proportions stated, and according to the
subsequent mode of treatment (that is, of moulding and pressing the
articles to be manufactured) I cause a larger or smaller quantity of
moisture to be added to or remain with the mass.

page_text: Having now described the nature of my said Invention, and the
manner in which the same may be carried into effect, I claim as my
Invention, the use of blast furnace slag in a state of fine division as the
preponderating ingredient in a mass which is composed of the same and
clay, and the manufacture therefrom of tiles, bricks, and other ceramic
articles in the manner substantially as described above.
In witness whereof, I, the said Carl Friedrich Claus, have hereunto
set my hand and seal, this
day of June, in the year
of our Lord One thousand eight hundred and seventy-three.
CARL. FRIEDRICH CLAUS. (L.s.)