CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF CEMENT
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
KEATING, of North Mews, Fitzroy Square, in the County of Middlesex,
Scagliolist, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eleventh day of February, in the ninth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
John Keating, my exors, adñññors, and assigns, Her especial licence, full power,
sole privilege and authority, that I, the said John Keating, my exors, admors,
and assigns, or such others as I, the said John Keating, my exors, admors,
or 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 "CERTAIN IMPROVEMENTS
IN THE MANUFACTURE OF CEMENT;" in which said Letters Patent is contained
a proviso that I, the said John Keating, shall cause a particular description
of the nature of my said Invention, and in what manner the same is to be
performed, to be inrolled in Her said 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 appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said.
John Keating, do hereby declare that the nature of my said Invention, and

page_text: the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, that is to say: -
My Invention consists of combining gypsum (sulphate of lime) or other
calcareous substance with borax, and then subjecting them to heat. And in
order that my Invention may be most fully understood and readily carried
into effect, I will proceed to describe the means pursued by me. I tako
lumps of gypsum or other calcareous substance, and by means of heat drive
off the waters of crystallization, as, is well understood in the manufacture of
plaster of Paris, and I cause the same to be combined with borax in the
following manner :-I take at the rate of five pounds of borax and dissolve it
in three gallons of water, and when dissolved, or as near thereto as possible, I
add three gallons more water, keeping this solution well stirred for about a day.
I also dissolve five pounds of cream of tartar in six gallons of water, keeping
this solution also well stirred for about the same time, and I combine the two
solutions, stirring them well together, until they are thoroughly mixed. I
would here remark, that although I prefer to use the cream of tartar, it is not
essentially necessary to do so, but I believe a better result is thereby
obtained. Into this combined solution I put the lumps of gypsum or other
calcareous substance (deprived of the water of crystallization), taking care that
the same. are sufficiently covered, and there let them remain until the same
become thoroughly impregnated or saturated with the solutions. I then
remove the lumps, and they will then be in a state to be introduced into an
oven or furnace, raised to a red head, visible by daylight. The lumps are to
remain in the oven in that state for about six hours, and are then to be
removed from the oven or furnace and allowed to cool down, when they are to
be reduced to powder like other cements. The lumps of gypsum or other
calcareous substance, when deprived as aforesaid, may be used when reduced
to a powder, in which case the powder to be thoroughly mixed with the
aforesaid combined solutions until the same be brought to a paste or like
dough, and then, having made such paste into lumps, such lumps are to be
submitted to a red heat, and afterwards reduced to powder, like the lumps of
gypsum, as before mentioned.
Having thus described the nature of my Invention, and the manner in
which the same is performed, I would wish it to be understood that I do not
confine myself to the exact details, so long as the peculiar character of my
Invention be retained. And I would state, that I am aware that cements
have been before made from gypsum or other calcareous substance by com-
bining them with acids, alkalies, and also with alum, and the same have been
afterwards calcined; and I mention these in order to state that.I have found

page_text: the use of borax peculiarly applicable in the making of cement when combined
with gypsum or other calcareous substance, and subjected to heat. And I
would wish it to be understood that what I claim is, the mode of mauu-
facturing cement by, combining gypsum or other calcareous substance with
borax, and subjecting them to heat, as herein described.
In witness whereof, I, the said John Keating, have hereunto set my
hand and seal, this Tenth day of August, in the year of our Lord One
thousand eight hundred and forty-six.