IMPROVE- MENTS IN THE MANUFACTURE OF PORTLAND CEMENT
Year: 1864

page_text: LETTERS PATENT to John Cleaver, of No. 9, Canterbury Place, Walworth,
in the County of Surrey, Gentleman, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF PORTLAND CEMENT."
Sealed the 23rd June 1865, and dated the 28th December 1864.
PROVISIONAL SPECIFICATION left by the said John Cleaver at the Office
of the Commissioners of Patents, with his Petition, on the 28th December
1864.
I, JOHN CLEAVER, of No. 9, Canterbury Place, Walworth, in the County
of Surrey, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF PORTLAND CEMENT," to be as
follows:-
Whereas the mud deposited on the banks or borders of different rivers
varies in its composition and is only in a few instances originally adapted for
the manufacture of Portland cement in consequence of the deficiency of silica,
I cause the deposit or mud intended to be used to be carefully analysed, and
having ascertained the relative proportions of silica and alumina, I cause to be

page_text: added to the deposit or mud so analysed, so much silica either in a soluble or
insoluble state as will form a mixture of the following proportions:-Silica 60
or 65 per centum, alumina 35 or 30 per centum upon every ton of the mixture
which will then be applicable to the manufacture of portland cement. By this
means I am enable to use any kind of aluminous or silicious mud for manu-
facturing Portland cement.
The method of securing a uniform mixture of the silica and alumina is as
follows: I cause the silica to be reduced to a fine powder if necessary, and
intimately mix the same by means of a wash mill or other suitable contrivance
with the mud or deposit intended to be used, when so mixed I run off the
whole into a settling pit where it remains until it has sufficiently settled
down to allow the water to be drawn off. In this state I use the mixed silica
and alumina by washing it in the ordinary wash mill with the necessary pro-
portion of lime or carbonate of lime (chalk), that is to say, to every ton of
mud I add 5 or 6 tons of chalk according to the moisture of the chalk, or if
lime be used, then from 3 to 3 tons of lime to every ton of mud. After
exposing the last-mentioned mixture to a high temperature a combination
takes place forming a silicate of lime and alumina (or Portland cement).
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Cleaver in the Great Seal Patent Office on the 26th
June 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, J, JOHN CLEAVER,
of No. 9, Canterbury Place, Walworth, in the County of Surrey, Cement
Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of December, in the year of our
Lord One thousand eight hundred and sixty-four, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Cleaver, Her special licence that I, the said John Cleaver,
my executors, administrators, and assigns, or such others as I, the said John
Cleaver, 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 "IMPROVEMENTS IN THE MANU-
FACTURE OF PORTLAND CEMENT," upon the condition (amongst others) that I, tho

page_text: par-
said John Cleaver, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
ticularly 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 Cleaver, 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 :—
Whereas the mud deposited on the banks or borders of different rivers
varies in its composition and is only in a few instances originally adapted for
the manufacture of Portland cement in consequence of the deficiency of silica,
I cause the deposit or mud intended to be used to be carefully analyzed, and
having ascertained the relative proportions of silica and alumina, I cause to be
added to the deposit or mud so analized, so much silica, either in a soluble or
insoluble state, as will form a mixture of the following proportions:-Silica 60
or 65 per centum, and alumina 35 or 30 per centum upon every ton of the
mixture, and which mixture will then be applicable to the manufacture of
Portland cement. By this means I am enabled to use any kind of aluminous
or silicious mud for manufacturing Portland cement.
The method of securing a uniform mixture of the silica and alumina is as
follows: I cause the silica to be reduced to a fine powder if requisite, and
intimately mix the same by means of a wash mill or other suitable contrivance
with the mud or deposit intended to be used; when so mixed I run off the
whole into a settling pit where it remains until it has sufficiently settled down
to allow the water to be drawn off; in this state I use the mixed silica and
alumina by washing it in the ordinary wash mill with the necessary pro-
portion of lime or carbonate of lime (chalk) that is to say, to every ton of
nud I add five tons and ten hundredweight or six tons of chalk according to
the moisture of the chalk, or if lime be used then I add from three tons to
three tons and ten hundredweights of lime to every ton of mud. After
exposing this last-mentioned mixture to a high temperature, a combination
takes place forming a silicate of lime and alumina or Portland cement.
Having now described the nature of my said Invention, and in what manner
the same may be performed, I declare that I claim,-
Firstly, the principle of utilizing any silicious or aluminous deposit for the
purpose of manufacturing Portland cement thereout by means of the analytical
process herein-before described.

page_text: Secondly, I would have it understood that I do not confine myself to the
.exact details herein described so long as the peculiar character of my Invention
be retained.
In witness whereof, I, the said John Cleaver, have hereunto set my
hand and seal, this Twenty 24th day of June, in the year of our Lord
One thousand eight hundred and sixty-five.
Witness to the signature of
the said John Cleaver,
THOMAS BAKER,
Cement Maker,
Burgh Castle,
near Great Yarmouth.
JOHN CLEAVER. (L.S.)