AN IMPROVED FIRE RESISTING CEMENT
Year: 1885

page_text: I, WILLIAM MONTGOMERY of N° 11 St. James Street in the City and County of
Newcastle-upon-Tyne, Draughtsman, do hereby declare the nature of my invention
for AN IMPROVED FIRE RESISTING CEMENT, to be as follows:-
I form my cement in 2 parts one as a powder, and the other as a paste.
The powder, which in cement work is technically called the aggregate, I form of
finely ground porcelain, or pottery waste, about 50 parts in 100; finely ground and
long kept Portland Cement of best quality about 40 parts in 100; and ground red
lead, about 10 parts in 100.
The paste I form of very finely ground porcelain, or pottery waste mixed with a
small percentage (about 5 per cent does very well) of finely ground plumbago.-I
form this into a paste with water containing a flux such as Borax and a small
proportion of Silicate of Soda, the whole being mixed in a vat so as to be a little
softer than putty.
In using the cement the proportions of paste and aggregate are varied according
to the purpose to which it is to be applied and for certain purposes the paste may
be used alone.

page_text: I, WILLIAM MONTGOMERY of N° 11 St. James Street, Newcastle-upon-Tyne
Draughtsman, do hereby declare the nature of my invention for AN IMPROVED
FIRE RESISTING CEMENT, and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement :-
I form my Cement in two parts one as powder and the other as a paste.-The
powder which in cement work is technically called the aggregate, I form of finely
ground porcelain, or pottery waste about 50 parts in 100, finely ground and long
kept Portland Cement of best quality about 40 parts in 100, and ground red lead
about 10 parts in 100.
The paste I form of very finely ground porcelain or pottery waste, mixed with a
small percentage (about 5 per cent does very well) of finely ground plumbago.-I
form this into a paste with water containing a flux such as Borax and a small
proportion of silicate of soda the whole being mixed in a vat so as to be a little
softer than putty.
In using the cement the proportions of paste and aggregate are varied according
to the purpose to which it is to be applied and for certain purposes the paste may
be used alone.
Having thus described the nature of my invention I will proceed more par-
ticularly to describe the manner in which the same is to be carried out.-I first
desire to remark that the proportions of the ingredients used may be varied within
considerable limits according to the heat to which the finished cement is to be
subjected and the purpose for which it may be required, and that some of those I
have mentioned may for certain purposes be dispensed with or replaced by other
ingredients such for instance as the red lead, the plumbago, and the Borax (altho'
for other purposes these ingredients are of great value) but the essential points of
my invention are the use of ground porcelain or pottery waste which has been
subjected to extreme heat as the "aggregate" to be mixed with portland cement,
and the use of silicate of soda in solution to make it fire resisting.
When the cement is to be used for the purpose of making a fire resisting material
not exposed to an extreme heat 1 increase the proportions of flux and when
extreme heat is required I reduce it.
As an example of the various uses of the ingredients I have mentioned I will
describe the method of making cement slabs to be enamelled for mantle pieces and
for other similar uses and the method of making foundations, for chemical brick
work pans or furnaces, and the method of constructing fabrics for extreme heat as
follows:-
For Cement Slabs 1 mix equal parts of finely ground and long kept Portland
Cement with my aggregate of ground porcelain or pottery waste and when tempered
with a very little water I beat the whole carefully into a mould so as to get it to
set together with as little water as possible and as closely as may be, when the
slab is set and dried dip it in a bath of the before mentioned paste diluted with
water, and then allow it to dry again; it thus becomes a fire resisting material
adequate to endure the heat of an enamelling furnace while at the same time it

page_text: procures great tenacity and hardness and I can by this means form of a cheap cement
many articles of ornament and use such as are usually made of more costly slate
and in which mouldings are produced by a mould instead of as with slate by
carving. When the slab is thus prepared I subject it to such coloring and
enamelling process as may be desired in the ordinary way in which slate slabs are
treated and enamelled.
For the foundations of chemical pans or furnaces I use aggregate and cement as
before described with such proportions of ground red lead and borax as will
slightly flux it at the heat it is required to bear with plumbago to diminish the
tendency to crack and silicate of soda to prevent the destructive action which fire
has on ordinary Portland Cement. For fabrics subjected to extreme heat I increase
the proportions of aggregate to the portland cement I omit the borax and reduce
the quantity of the red lead so as to avoid fluxing too easily and I saturate the
structure after its construction and drying with a solution of Silicate of Soda once
or more times.
It is convenient to make up the materials when intended for use at a distance
from the manufactory in the form of dry powder and paste as set forth in in the
beginning of my Specification so that the mixture of the ingredients may be
thorough and that the proportions may not vary by carelessness of the men mixing
them.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
In a fire resisting cement the use of an aggregate composed of finely ground
porcelain or pottery waste which has been subjected to extreme heat, Portland
cement and silicate of soda with or without the other ingredients specified,
substantially as described.