IMPROVEMENTS IN PLOUGHS
Year: 1859

page_text: LETTERS PATENT to John Fraser, of the Town and County of Banff,
North Britain, Manager of the Banff Iron Foundry, for the Invention
of "IMPROVEMENTS IN PLOUGHS."
Sealed the 29th April 1859, and dated the 5th March 1859.
PROVISIONAL SPECIFICATION left by the said John Fraser at the
Office of the Commissioners of Patents, with his Petition, on the 5th
March 1859.
I, JOHN FRASER, of the Town and County of Banff, North Britain,
Manager of the Banff Iron Foundry, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN PLOUGHS," to be as follows, that is to say :-
This Invention relates to the manufacture of what are technically known as
the "mould boards" of ploughs, in such a manner as to have one portion
harder than the rest. The part exposed to severe wear is chilled in the
casting, whilst the other part is left soft. In carrying out this system in
practice two casts in plaster of Paris or other suitable material or composition
are primarily taken from that portion of the mould board which is to
be hardened. One of these casts is used in conjunction with common.
moulding sand to make the pattern from which to cast the mould boards..
From the other the chill for hardening the casting is cast. This secures a.
correspondence between the pattern and the chill, and the result is that a. good
and accurate casting is obtained, with the wearing portion very hard,. whilst
the rest is as soft as is necessary for its particular office..

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Fraser in the Great Seal Patent Office on the
5th September 1859.
TO ALL "TO WHOM THESE PRESENTS SHALL COME, I, Jonn
FRASER, of the Town and County of Banff, North Britain, Manager of the
Banff Iron Foundry, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of March, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said John Fraser, Her special license that the said
John Fraser, my executors, administrators, and assigns, or such others as
I, the said John Fraser, my executors, administrators, or 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 "IMPROVEMENTS IN PLOUGHS," upon the condition
(amongst others) that I, the said John Fraser, 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 Fraser, do hereby declare the
nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, that is to say :-
:
My said Invention relates to the manufacture of what are technically known
as the "mould boards" of ploughs, in such a manner as to have one portion
harder than the rest. The part exposed to severe wear is chilled in. the
casting, whilst the other part is left soft. In carrying out this system in
practice, two casts in plaster of Paris or other suitable material or composition
are primarily taken from that portion of the mould board which is to be
hardened. One of these casts is used in conjunction with common moulding :
sand, to make the pattern from which to cast the mould boards; from the
other the chill for hardening the casting is cast. This secures a correspon-
dence between the pattern and the chill, and the result is that a good and

page_text: accurate casting. is obtained with the wearing portion very hard, whilst the
rest is as soft as is necessary for its particular office.
65
And in order that my said Invention may be properly understood, I shall
now proceed to describe in fuller detail how it may be judiciously carried out
in actual practice. In order to prepare or manufacture the mould boards of
ploughs according to my improved system or mode, it is necessary to make a
chill" or casting forming a reverse of that part of the mould board which
is more particularly exposed-to wear, in order that that portion may be made
as hard. as possible, so that it may withstand the more severe work to which it
is exposed. The part which wears away the soonest in the mould board
varies.to. some.extent.according to its particular shape, so that attention must
be directed, in the first instance, to the particular conformation of the mould
board, in order that the cast for the "chill" may be adapted to the precise
part of the mould board which it is desired to harden. In preparing mould
boards for chilling, two casts in plaster of Paris or other suitable plastic or
moulding composition or material are taken from that part of the mould
board which is to be hardened. One of these casts serves as a pattern for the
chill, and for this purpose it is embedded in moulding sand, in a suitable flask
or moulding box, the upper part of which is "parted" in the usual manner, and
the pattern is taken out. The two parts of the moulding box are again put
together, and the chill is cast in the ordinary way. The other cast is used in
conjunction with moulding sand, to form the mould or "caulm" in which a
mould board is cast, which is used as the pattern board in the final operation
of casting from the chill. In preparing the mould for casting from, the
"chill" is suitably disposed in the moulding sand, so as to insure an exact
correspondence or uniformity between the pattern and "chill." In this way
when the casting operation takes place, which is effected in the usual manner,
the "chill" by its rapid abstraction of the heat serves to harden the mould
board at the part exposed to the greatest amount of wear, resulting in the
production of mould boards greatly superior in point of efficiency to those of
the ordinary inake.
Having now described and particularly ascertained the nature of my said
Invention and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider novel and original,
and therefore claim as the Invention secured to me by the herein-before in
part recited Letters Patent, is,-
First, the system or mode of manufacturing or producing the mould boards
of ploughs, in which the part or parts exposed to the greatest amount of
ear is or are rendered much harder than the surrounding metal, by the

page_text: means and in the manner herein-before described or any mere equivalent
therefor.
Second, the system or mode of hardening a portion of the mould boards
of ploughs by means of "chills," in order to render the wear of the same
uniform throughout, as herein-before described.
In witness whereof, I, the said John Fraser, have hereunto set my hand
and seal, this Third day of September, One thousand eight hundred
and fifty-nine.
JOHN FRASER. (L.S.)