A NEW AND IMPROVED MODE OF DRYING TILES, BRICKS, RETORTS, AND SUCH LIKE WORK MADE FROM CLAY AND OTHER PLASTIC SUBSTANCES
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
AINSLIE, of Redheugh, near Dalkeith, in North Britain, Farmer, send
greeting.
WHEREAS I did by petition represent unto Her most Excellent Majesty
Queen Victoria, that I had, after much study and expense, invented "A NEW
AND IMPROVED MODE OF DRYING TILES, BRICKS, RETORTS, AND SUCH LIKE WORK
MADE FROM CLAY AND OTHER PLASTIC SUBSTANCES," and Her said Majesty, being
willing to encourage all useful inventions, did issue Her Letters Patent under
the Great Seal of Great Britain, bearing date at Westminster, the Thirtieth
day of September, in the year One thousand eight hundred and forty-three,
in the seventh year of Her reign, whereby Her Majesty did, for Herself, Her
heirs and successors, give and grant unto me, the said John Ainslie, my
executors, administrators, and assigns, Her special permission, licence, and
full power, sole privilege and authority, that I, the said John Ainslie, my
executors, administrators, and assigns, by ourselves, or any other person to
whom I or they should grant permission, and to no others, during the term
of years therein expressed, should and lawfully might make, use, exercise,
and vend the said Invention within that part of the United Kingdom of
Great Britain and Ireland called England, Wales, the Town of Berwick-upon-

page_text: Tweed, and also in all IIer Majesty's Colonies and Plantations abroad; in which
said Letters Patent there is contained a proviso, obliging me, the said John
Ainslie, within the space of six calendar months from the date of the said
grant, by a writing under my hand and seal, enrolled in Her Majesty's High
Court of Chancery, particularly to describe and ascertain the nature of the
said Invention, and in what mode it is to be performed, otherwise the said
Letters Patent should become void, as the said Letters Patent in themselves
more fully bear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Ainslie, do hereby declare that the nature of my said Invention, and the
manner in which the same is to be performed, are described and ascertained
in manner following (that is to say) :-
The drying of clay formed into tiles and other articles at the ordinary tem-
perature and rate of motion of the atmosphere is a difficult and tedious process
at many seasons of the year, so that during the winter season the manufacture
of such articles is either altogether or in a great measure suspended. Now it
is well known that the drying depends on the rate of evaporation of the water
contained in the substances to be dried, that is, on the rate at which the water
can be converted into vapour, and on the removal of the vapour so gencrated,
the former of which depends on the temperature, and the latter on the rate of
motion of the surrounding air or of the current to which the substance to be dried
is subject; also, in order to dry any substance with the greatest rapidity, the
vapour must be removed as fast as it is formed, so as to prevent the evaporation
being checked by the presence of accumulated vapour. Now my Invention
consists in the application of the above well-known truths or principles to the
manufacture of tiles, bricks, or similar articles, so as to be able to carry on
such manufacture at all seasons of the year. For this purpose I place the clay
(when formed and ready to place on the shelf to dry according to the present
process of manufacture) in a close chamber heated to an artificial temperature,
and through which a current of air is made to pass by mechanical or other
means. The chamber which I have hitherto employed is built of bricks, and
so situate and arranged, that the clay, as taken from the machine or mould by
which it is formed into the required shape, is placed in a waggon or frame of
shelves, which frame travels along a railway. When the frame is filled, it is
run into the close chamber and left there, subject to the artificial current and
temperature, until the clay is sufficiently dried for burning. The time during
which the clay or plastic substance must be subjected to the process of drying
will depend on the nature and quality of the substance, and on the form into

page_text: which it is put, and on the temperature and current to which it is subject. I
find a temperature of about eighty degrees of Fahrenheit, and a current of
about six feet per second, to be a temperature and a velocity which answer
extremely well for general purposes; but the same may be varied at the con-
venience of the manufacturer, only taking care not to increase the temperature
and current to such an extent that the clay cracks in drying. And if from the
peculiar character or form of the clay the above temperature and rate of
current occasion the clay to dry unequally or to crack, the manufacturer must
decrease the temperature and current, according to the circumstances of the
case, so as to obviate that defect and allow the clay to dry more slowly. The
close chamber or house in which the clay is dried may be conveniently adapted
to the rate at which the clay can be made into the required form, so that a
frame or waggon of dried clay may be removed from one end of the house
or chamber to the kiln to be burnt to make room for the introduction of
the frame or waggon of moist clay at the other end. The close chamber
may be heated by flues at the bottom and sides, or by hot water and steam
pipes, or by the admission of hot air through small apertures, cold air being
let into the chamber at other apertures so as to mix with and regulate
the temperature of the heated air. The warm atmosphere of the chamber
may be set in motion by the draft of a chimney, or fanner worked by
steam, horse, or other power; or the current may be created by injecting or
withdrawing the air by pumps worked by power in the usual manner, the
mechanical details to be employed for that purpose being well understood, and
forming no part of my Invention. The close chamber or house, the method
of heating such chamber, and the creation of the current of air through it, and
the transfer of the clay to be dried through the close chamber, may be con-
structed, arranged, and adapted in various ways, according to the circumstances
of each case. And hereby declare that I do not claim the exclusive use of
the constructions, arrangements, and adaptations herein-before described and
referred to, except when the same are used in connection with and for the
purposes of my said Invention, of drying plastic substances in a close chamber
at an artificial temperature and under a current of air, as above described.
In witness whereof, I, the said John Ainslie, have hereunto set my
hand and seal, this Twenty-ninth day of March, in the year of our
Lord One thousand eight hundred and forty-four.
JOHN CONNELL, Witness.
ROB BARKWORTH, Witness.
JOHN AINSLIE. (L.S.)

page_text: AND BE IT REMEMBERED, that on the Twenty-ninth day of March,
in the seventh year of the reign of Her Majesty Queen Victoria, the said
John Ainslie came before our said Lady the Queen in Her Chancery, and
acknowledged the instrument aforesaid, and all and every thing therein con-
tained and specified, in form above written. And also the instrument
aforesaid was stamped according to the tenor of the Statute made in the fifty-
fifth year of the reign of His late Majesty King George the Third.
Inrolled the Twenty-ninth day of March, One thousand eight hundred and
forty-four.