AN IMPROVED METHOD OF CONSTRUCTING COCKS FOR STOPPING FLUIDS
Year: 1808

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, JOHN
DICKSON, of Edward Street, in the Parish of Christchurch, in the County of
Surrey, Engineer, sends greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent, under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-ninth day of March, in the forty-eighth year of
His reign, give and grant unto me, the said John Dickson, my executors,
administrators, and assigns, his especial licence, full power, sole privilege
and authority, that I, the said John Dickson, my executors, administrators,
and assigns, during the term of years therein expressed, should and lawfully
might make; use, exercise, and vend, within that part of the United King-
dom of Great Britain and Ireland called England, the Dominion of Wales,
and the Town of Berwick-upon-Tweed, my Invention of "AN IMPROVED
METHOD OF CONSTRUCTING COCKS FOR STOPPING FLUIDS;" in which said Letters
Patent there is contained a proviso obliging me, the said John Dickson, by
an instrument in writing under- my hand and seal, to particularly describe
and ascertain the nature of my said invention, and in what manner the
same is to be performed, and cause the same to be inrolled in His Majesty's

page_text: High Court of Chancery within one calendar month next and immediately
after the date of the said Letters Patent, as in and by the said Letters Patent,
referrence being thereunto had, may more fully and at large appear.
NOW KNOW YE, that, in compliance with the said proviso, I, the said
John Dickson, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be made and performed, are heroin-
after particularly described and ascertained, that is to say :-
Fig. 1 in the annexed Plan is an apparatus or cock constructed so as to
answer all the purposes of the common sluice and stop cocks for permitting
fluids to pass and repass as may be required, and by one operation to answer
the purpose of two separate cocks or valves, and which apparatus I claim as
my Invention.
Fig. 1. A is a plate or piece with two apertures C and D, of any given
dimensions, for permitting fluids to pass and repass from or to the pipe F,
as may be required. These apertures are of an oblong form, which I
consider the best, although they may be made of any other form. This plate
or piece A, and the other parts of the apparatus, may be made of brass, iron,
or any other metal or materials which may be found to agree best with the
nature of the fluids acting thereon, or the purpose for which the apparatus may
be wanted. The surface of the plate or picce A is made sufliciently even
and smooth on those parts which surround the apertures so as to be perfectly
air and steam tight, when the surface of the moveable plate or pieco B,
(which is to be equally even and smooth), comes in contact with it. The move-
able plate or piece B has a curve or space made or cut in the surface of it,
so as to be sufliciently wide to cover both the apertures C and D, and the
intermediate space in the face of the plate A, so that fluids may pass from or
into the apertures C and D at the same timo, by moving the plate or piece B
in a direction parallel with its surface. By a similar motion the communica-
tion C and D may be shut, and a communication opened at pleasure between
C or D alternately and the pipe F, which pipe contains the fluid to be
conveyed into or which passes through the apertures C and D alternately,
as may be required. G is the rod by which the plate or piece B is moved.
I is the stuffing box through which the rod G passes. His a spring pressing
against the rod G, for the purpose of keeping the plate or piece B in close
contact with the surface of the plate or piece A. It is also a guide for the
rod G.
Fig. 2 represents the said apparatus applied to a double-acting steam
engine, the application of which apparatus to steam engines I claim as my

page_text: presence of
JOHN EDWARDS.
AND BE IT REMEMBERED, that on the Twenty-second day of April, in
the year above mentioned, the aforesaid John Dickson 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.