IMPROVEMENTS IN THE MANUFACTURE OF CHINA, POTTERY, BRICKS, AND OTHER ARTICLES MANU- .FACTURED FOR THE MOST PART OF CLAY
Year: 1854

page_text: LETTERS PATENT to John Marriott Blashfield, of Millwall, Poplar, in
the County of Middlesex, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF CHINA, POTTERY, BRICKS, AND OTHER ARTICLES MANU-
.FACTURED FOR THE MOST PART OF CLAY."
Sealed the 22nd August 1854, and dated the 22nd June 1854.
PROVISIONAL SPECIFICATION left by the said John Marriott Blashfield
at the Office of the Commissioners of Patents, with his Petition, on the
22nd June 1854.
I, JOHN MARRIOTT BLASHFIELD, of Mill Wall, Poplar, in the County of
Middlesex, do hereby declare the nature of the Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF CHINA, POTTERY, BRICKS, AND OTHER ARTICLES. MANU-
FACTURED FOR THE HOST PART OF CLAY," to be as follows:-
My Invention has for its object the use of minerals or fossils containing
phosphate of lime in the manufacture of china and pottery, in place of burnt
bones; and also in making bricks and other articles composed for the most
part of clay. These fossils or minerals exist chiefly in what geologists term the
crag and the gault formations. They vary in color (when properly cleansed
and dried) from a pale yellow to a dark brown, and the fossil bone found
among them may, by cleansing and by burning, be rendered nearly white. By
chemical analysis, these minerals or fossils present from about 20 to 60 per
cent. of phosphate of lime; the fossil bones at times containing as much as 70
per cent. of phosphate of lime. Their other constituents are chiefly silica,

page_text: carbonate of lime, and alumina, with at times small quantities of pyrites of
iron, and some other substances."
To use these fossils or minerals with economy, for china and pottery purposes,
they should be dried after cleansing previous to reducing them to powder, or
they may be reduced in a mill with water without first drying. It is preferred
to take the fossils or minerals and place them in a cylindrical wash mill, and
to cleanse them thoroughly. The mill is of the form of a drum or cylinder,
pierced with small holes, for the dirt, grit,, and sand to escape; and the water
in the trough in which the cylinder revolves should be often changed.
The cylinder has a door on the side of the cylinder for charging with and
discharging the minerals. The cylinder is caused to revolve on an axis in a
trough containing water. The axis on which the cylinder revolves has numerous
spikes or projections, and there are also spikes or projections on the interior of
the cylinder. Both cylinder and axis may revolve, and in opposite directions.
The drum or cylinder is preferred to be made of gutta percha. Other modes
of washing may, however, be resorted to.
After the fossils or minerals have been washed, they are placed in a warm
chamber to dry, at a temperature of about 200° Fahrenheit.
For using fossils or minerals of this nature with brick earth, to render bricks
and other articles made therefrom harder, and also for making bricks from such
fossils or minerals alone, it is preferred to employ kilns of the form of an
inverted cone, having an opening at the bottom and a grating of loose iron
bars. The fossils or minerals are strewn over the fire, which it is preferred
should be inade of small coal, or coke, or culm. The fuel and minerals are
arranged in alternate layers in the kiln. After the fossils or minerals have
been washed and dried, they are placed between crushing rollers, or beneath
stampers, or under edge stones or horizontal millstones, and reduced to a fine
powder, not less than what will pass through a sieve of 35 meshes to an inch.
For china pottery and fine work the reduction should be to a powder that will
pass through a sieve at least of 60 meshes to an inch; and for some work the
finest wire gauze should be used for sifting, and through these finer sieves the
powder should be washed by water. For the finest china and pottery it is
desirable that the powder should pass through sieves in which magnets or
electro-magnets are placed, so that all small particles of iron may be taken by
the magnets. It is preferred that the large bones should be picked out of the
fossil or minerals, and that after being washed they should be acted on by
steam,. then dried and reluced to powder.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Marriott Blashfield in the Great Seal Patent Office
on the 22nd December 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MARRIOTT BLASHFIELD, of Mill Wall, Poplar, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-second day of June, in the year. of our
Lord One thousand eight hundred and fifty-four, in the eighteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John, Marriott Blashfield, Her special licence that I, the said
John Marriott Blashfield, my executors, administrators, and assigns, or such
others as 1, the said John Marriott Blashfield; 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 expresseil, 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 MANUFACTURE OF CHINA, POTTERY, BRICKS,
AND OTHER ARTICLES MANUFACTURED FOR THE MOST PART OF CLAY," upon the
condition (amongst others) that I, the said John Marriott Blashfield, 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 I, the said John Marriott Blashfield, 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):-
My Invention has for its object the use of minerals or fossils containing
phosphate of lime, and known in commerce as "coprolites," "phosphorites,"
"fossil sponges,
," "fossil foeces," "fossil flesh;" and "fossil bones," which are
said to be the remains of extinct animals, in the place of burnt bones, in the
manufacture of china and pottery; and also in making bricks, tiles, and other
articles composed chiefly of clay. These fossils or minerals exist chicfly in
what geologists term the crag, gault, and lias formations. They generally vary
in colour, when properly cleansed and dried, from a pale yellow to a dark brown,
but the fossil bones are frequently white. By chemical analysis, these minerals

page_text: or fossils are found to contain from twenty to sixty per cent. of phosphate of
lime; the fossil bones at times contain as much as seventy per cent. of phos-
phate of lime. The other constituents are chiefly silica, carbonate of lime,
alumina, and at times small quantities of peroxide of iron, iron pyrites, and
other substances. For the purpose of cleansing these fossils or minerals, it is
preferred to place them in a cylindrical wash mill, which consists of a perforated
drum or cylinder, revolving in a trough of water, to facilitate the escape through
the perforations of the cylinder of the dirt, grit, and sand with which the fossils
are generally surrounded. The water in the trough in which the cylinder
revolves should be constantly renewed. The cylinder should have a door for
charging and discharging the fossils or minerals. The axis on which the
cylinder revolves is furnished with numerous spikes or teeth, and there are also
spikes or teeth on the inner surface of the cylinder. If desired, both cylinder
and axis may be made to revolve in opposite directions. Care must at all
times be taken that the cylinder be not charged with minerals or fossils of too
large a size to pass between the teeth.
After the fossils or minerals have been washed, they are (if intended for the
manufacture of china or the finer classes of pottery) placed in a warm and well
ventilated chamber, upon earthen tiles, above hot air flues, to dry, at a tem-
perature of about three hundred degrees of Fahrenheit, which temperature
should not be greatly exceeded; but for using fossils or coprolites in the
manufacture of bricks, tiles, and other articles of coarse pottery, I prefer for
drying the same the use of kilns of the form of an inverted cone, having at the
bottom a grating of loose iron bars, which are removable when the kiln is
discharged. The fire should be made at the bottom of the kiln on the iron
bars, and the fossils or coprolites strewed thereon; then another layer of fuel,
and so on, in alternate layers, until the kiln is filled, and I use coke or culm in
preference to coal as fuel. The proportion of coke most advantageous is
112 lb. to two tons of fossils or coprolites, and when the fossils are dried in
this manner it is necessary to separate the ashes from the dried fossils by
sifting.
For the finest pottery, such as china and porcelain, I would recommend that
out of the fossils or coprolites all the clean large bones should be picked, and
that these fossil bones should be cleansed, first by washing, as before described,
and then by steam. To effect the cleansing by steam, I place them in a
cylinder revolving on its axis, and at one end of the axis the steam enters and
at the other end it passes out. The exit hole should be covered with wire
gauze, of about eight meshes to the inch, to prevent pieces blowing through.
Steam at high pressure should be used, and the bones will by the action of the

page_text: steam be broken as well as cleansed. After the fossils or minerals have been
washed and dried, as herein-before described, they are placed between crushing
rollers, or beneath stampers, or under edged stones, or horizontal millstones,
or in other suitable manner reduced to a powder that will pass readily through
a sieve with thirty-five meshes to an inch. But when intended for the
manufacture of terra cotta and other pottery of a fine or comparatively fine
description, the fossils or minerals should be reduced to a powder that will pass
through a sieve of sixty meshes to an inch; and for china, and the best descrip-
tions of pottery work, sieves of the finest wire gauze or other material should
be used; the sifting being facilitated by washing in the ordinary manner of
preparing materials for the manufacture of china.
It sometimes, or rarely, occurs, that the fossils or coprolites contain or
are mixed with particles of metallic iron. Now, where such fossils or coprolites
are to be employed in the manufacture of the, finer classes of articles it is
desirable to separate these particles of iron, and the best means which I am
acquainted with for effecting this is to cause the fossils or coprolites when in
powder to pass between or near the poles of small electro-magnets, which will
retain the particles of iron; or the same result may be obtained by spreading
the ground fossils or coprolites in a thin layer, and raking it over with a suitable
combination of small electro-magnets. The fossil or mineral cleaned and dried
in the manner before described should afterwards be analyzed, if its composition
is not already known, so that, when it is used in the manufacture of china or
pottery ware, a just proportion may be maintained between the phosphate of
lime, the carbonate of lime, the silica, and the alumina; and the proportions to
be maintained are those usually maintained by potters between these ingre-
dients when phosphate of lime from ordinary burnt bones is employed; and it
sometimes happens that fossils or coprolites are found which naturally contain
phosphate and carbonate of lime, silica, and alumina, in such proportions, that,
when cleansed and ground, they may, without any addition of other substances,
be manufactured into pottery ware. The mixture of materials (either artificial
or natural) may be moulded, when in a plastic state, into articles in the ordinary
manner, and such articles will be less liable to warp or twist in burning than
articles made from a mixture containing bone ash.
I would here remark, that it has heretofore been found practically impossible
to mould articles of any size from dry materials by pressure between dics, (that
is to say,) by the process generally known as
"Prosser's patent process,")
when the materials contain bone ash, in consequence of the articles so mouliled
warping and twisting in burning; but if, in place of adding bone ash, the
requisite phosphate of lime is supplied to the mixture in the fossil state,

page_text: articles formed from it will burn (if the ordinary precautions are taken)
without warping or twisting.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I do not confine myself
to the exact details described; but what I claim is, the use of minerals or
fossils containing phosphate of lime, and known in commerce as "coprolites,"
phosphorites," "fossil sponges," "fossil fœces," "fossil flesh," and "fossil
bones," in the manufacture of china, pottery, bricks, and other articles of which
clay is the principal ingredient.
In witness whereof, I, the said John Marriott Blashfield, have hereunto
set my hand and seal, this Twenty-first day of December, in the year
of our Lord One thousand eight hundred and fifty-four.
Witness,
J. T. HARSTON,
12, Cursitor Street,
Chancery Lane.
J. M. BLASHFIELD. (8.)