AN IMPROVEMENT IN THE MANUFACTURE OF EARTHENWARE, CHINA, AND PORCELAIN.
Year: 1855

page_text: LETTERS PATEN
to Nathan Hackney, or 20, IN
Invention of "AN IMPROVEMENT IN THE MANUFACTURE OF EARTHENWARE,
CHINA, AND PORCELAIN.
Sealed the 10th August 1855, and dated the 12th June 1855.
PROVISIONAL SPECIFICATION left by the said Nathan Hackney at the
Office of the Commissioners of Patents, with his Petition, on the 12th
June 1855.
I, NATHAN HACKNEY, of 20, North Street, Hull, do hereby declare the
nature of the Invention for "AN IMPROVEMENT IN THE MANUFACTURE OF
EARTHENWARE, CHINA, AND PORCELAIN," to be as follows:-
This Invention has for its object an improvement in 'the manufacture of
earthenware, china, and porcelain, and consists of the application of the
mineral or natural product borate of lime in the manufacture of earthenware,
china, and porcelain. For this purpose the borate of lime is ground or
reduced to powder, and it is preferred, particularly for the finer qualities of "

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Nathan Hackney in the Great Seal Patent Office on the
12th December 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, NATHAN
HACKNEY, of 20, North Street, Hull, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of June, in the year of our Lord One
thousand eight hundred and fifty-five, in the eighteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant. unto me, the
said Nathan Hackney, Her special licence that I, the said Nathan Hackney,
my executors, administrators, and assigns, or such others as I, the said Nathan
Hackney, 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 "AN IMPROVEMENT 'IN
THE MANUFACTURE OF EARTHENWARE; CHINA, AND PORCELAIN," upon the condition
(amongst others) that I, the said Nathan Hackney, by an instrument in writing
under my hand and seal, 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, 1, the said, Nathan.. Hackney,, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement thereof (that is to say) :-
This Invention -has-for-its object an improvement in the manufacture of
earthenware, china, and porcelain, and consists of the application of the
mineral or natural product borate of lime in the manufacture of earthenware,
china, and porcelain. For this purpose the borate of lime is ground or reduced
to powder, and it is preferred, particularly for the finer qualities of ware, to
wash the ground or reduced product with water.
Having thus stated the nature of my said Invention; I will proceed more
fully to describe the manner of performing the same. In preparing glaze
used in the manufacture of earthenware, china, and porcelain as heretofore
practised, it has been usual to employ borax (borate of soda) combined with
Cornwall stone, flint, whiting, and other matters. Now, the object of my

page_text: Invention is to employ, native borate of lime with soda-and other matters in
the making of glaze for such manufactures in place of borax, which is, as is well
known, a manufactured article, and the use of it in making of glaze is more
costly than the use of borate of lime. Different manufacturers have heretofore
when using borate of soda, had different compounds or mixtures for producing
glaze;
and it is probable that such difference of opinion will prevail with
different manufacturers hereafter when employing native borate of lime with
soda and other matters for making glaze. I will, however, hereafter state the
mixtures which I have employed and find fully to answer; at the same
time I do not confine myself thereto, as the same may be varied or other
mixtures may be used according to my Invention when employing native
borate of lime...
In preparing the borate of lime to be used according to my Invention in the
making of glaze, it is first reduced to powder, and, by preference, well washed
with water and then dried; but it is not essential that the washing should be re-.
sorted to. To the dry powder of borate of lime washed or unwashed I add about
25 per cent. of bicarbonate of soda, or its equivalent of soda ash or crystal soda,
and I mix these together mechanically. And in making up a glaze, if the matters
are to be calcined in saggars, I take at the rate of about 75 lbs. of Cornwall
stone, 45 lbs. of borate of lime mixed with bicarbonate of soda as above, 25 lbs.
of flint, 9 lbs. of whiting, 15 lbs. of soda crystals, and I calcine the mixture as
when using borax, and then add 30 lbs. of white lead, 4 ozs. of cobalt or stain.
When the calcining process is to be in a reverberatory furnace or fritt kiln, I
take at the rate of about 50 lbs. of Cornwall stone, 45 lbs. of borate of lime
mixed with bicarbonate of soda as above, 25 lbs. of flint, 15 lbs. of soda crystals,
and I calcine the mixture in the usual manner, and as when using borax; and
I then add 9 lbs. of whiting, 25 lbs. of Cornwall stone, 30 lbs. of white lead,
4 ozs. of cobalt or stain. The glaze made when employing borate of lime in
place. of borax is used by the manufacturer as heretofore, and as is well
understood; but by reason of the use of native borate of lime in place of
borax, a considerable saving will be effected in the manufacture.
Having thus described the nature of my said Invention, and the manner of
performing the-same, I would have it understood that I make no claim to the
use of the ingredients above named in the manufacture of glaze except the
native borate of lime. And the process of calcining, whether in saggars or
reverberatory.furnaces, or fritt.or fret-kiln,-is-in the-same way as that practised
when using borate of-soda (borax), and is not therefore separately-claimed by
me as of my Invention; but what I claim is, the application of native borate

page_text: of lime in the manufacture of glaze used by earthenware, china, and porcelain
manufacturers.
In witness whereof, I, the said Nathan Hackney, have hereunto set
hand and seal, this Twenty-seventh day of November, in the year
of our Lord One thousand eight hundred and fifty-five.
my
Witness,
S. CARPMAEL.
NATHAN HACKNEY. (L.S.)