INVENTION AND IMPROVEMENT OF TINNING, OR COVERING WITH TIN, SHEETS OR PLATES OF COPPER, BRASS, OR ZINK
Year: 1817

page_text: TO. ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
PARNALL, of the Parish of Saint Austell, in the County of Cornwall, Brazier,
send greeting.
WHEREAS. His most Excellent Majesty King George the Third, by His
Letters Patent, under the Great Seal of Great Britain, bearing date at
Westminster; the Tenth day of June, in the fifty-seventh year of His reign,
did give and grant unto me, the said John Parnall, His special licence, full
power,
sole privilege, and authority that I, the said John Parnall, my exe-
cutors, administrators, and assigns, should and lawfully might, during the
term of years therein expressed, make, use, exercise, and vend, within that
part of His Majesty's United Kingdom of Great Britain and Ireland called
England, His Dominion of Wales, and Town of Berwick-upon-Tweed, my
"INVENTION AND IMPROVEMENT OF TINNING, OR COVERING WITH TIN, SHEETS OR
PLATES OF COPPER, BRASS, OR ZINK;" in which said recited Letters Patent is
contained a proviso, obliging me, the said John Parnall, by an instrument in
writing under my hand and seal, to cause a particular description of the
nature of my Invention, and in what manner the same is to be manufactured
and performed, to be inrolled in His Majesty's High Court of Chancery,
within two calendar months after the date of the said Letters Patent, as in
and by the said Letters Patent, relation being thereunto had, may more fully
appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Parnall, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be manufactured and performed, is
described and demonstrated in manner following, that is to say :-.
Copper, brass, or zink may be tinned in plates in the same manner that
iron is now usually done, and which will occasion a large consumption of the

page_text: said metals, and will be much more durable than when manufactured as here-
tofore, for by the present method, copper, brass, or zink cannot be tinned when
in the form of plates. My process is this:-The sheet of copper, brass, or
zink must be bent for the purpose of placing it upon the edge, and then put
into a trough in which there is a preparation of two pints of spirits of salts or
marine acid to three gallons of water, more or less, according to the quantity of
the copper, brass, or zink, then put into an air furnace, heated with coal or
other fuel to raise a scale. The sheets are then taken out of the furnace, and
several of them put together, and taken up with tongs and struck upon an
iron plate until the scale is beaten off. The whole of this process must be
repeated until the original surface is taken off and the sheet appears clean.
The sheet must then be passed through a pair of case-hardened iron rolls,
turned very correctly to harden the metal, and give it a flat and smooth sur-
face. From thence the sheet or sheets must be taken and placed in troughs
of lees of fermented bran, which may be produced by placing the said bran and
water over flues through which the fire or heat from a stove passes to bring
the said bran mixed with water into a proper state of fermentation. This
process requires at least the space of four days' time previous to the lees being
used. The sheet of copper, brass, or zink must remain in the troughs of lees
twenty-four hours, and then put into a trough in which there is a preparation
of two pints of vitriolic acid to two gallons of water, or such a quantity as the
quality of the metal may require, in which the sheet must lie four hours, and
must be washed until it is cleansed. It then must be put into a trough of
clean water, and rubbed with water and sand until perfectly clean, then placed
again into troughs of clear water, from whence it is to be taken and dipped
into a pot of melted tin with tallow grease, or any other, more fit fat material
on the top, through which the sheet of copper, brass, or zink passes to the tin;
or otherwise, without tallow, grease, or any other more fit material on the top
of the tin, when the quality of the copper, brass, or ziuk makes it unnecessary.
After this the sheet of copper is dipped, if required, into a second tin or wash
pot filled with melted tin, and then into a pot of grease to take off' any knob of
tin that may have collected, and make the covering of tin of a smooth sur-
face. The sheet is then taken and rubbed clean with bran, and after this it is
passed through a pair of case-hardened high polished iron rolls, when it becomes
fit for usc.
In witness whereof, I have hereunto set my hand and seal, this
Nineteenth day of July, in the year of our Lord One thousand eight
hundred and seventoon
JOHN PARNALL. (L.S.)

page_text: AND BE IT. REMEMBERED, that on the same Nineteenth day of
July, in the year above mentioned, the aforesaid John Parnall came before
our Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained, in form above written.
And also the Specification aforesaid was stamped according to the tenor of
the Statute in that case made and provided.