IMPROVEMENTS IN THE ART OF MAKING AND WORKING PLOUGHS OF ANY KIND OR DESCRIPTION
Year: 1813

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
COOKE, of Greenwich, in the County of Kent, Esquire, send greeting.
WHEREAS His most Excellent Majesty King George the Third, by His
Letters Patent under the Great Seal of Great Britain, bearing date the
Fifteenth day of June, in the fifty-third year of His reign, did, for Himself,
His heirs and successors, give and grant unto me; the said William Cooke,
His especial licence that I, the said William Cooke, my executors, adminis-
trators, or assigns, or such others as I, the said William Cooke, my executors,
administrators, or assigns, should at any time agree with, and no others, from
time to time and at all times during the term of years therein expressed,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my "IMPROVEMENTS IN THE ART
OF MAKING AND WORKING PLOUGHS OF ANY KIND OR DESCRIPTION;" in which said
Letters Patent there is contained a proviso obliging me, the said William
Cooke, by an instrument in writing under my hand and seal, particularly to
describe and ascertain the nature of my said Invention, and in what manner
the same is to be performed, and to cause the same to be inrolled in His
Majesty's High Court of Chancery within two calendar months next and
immediately after the date of the said recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
William Cooke, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, is described and
ascertained in the plans hereunto annexed, and the following explanation
thereof, that is to say :-

page_text: The desiderata for a good plough are, that it, should easily penetrate the
earth, cutting, both vertically and horizontally, with the least possible expence
of labour, and, after so cutting it, to raise it from its primitive bed to an angle
gradually ascending from the point and from the furrow side of the plough, till
the earth reaches a proper elevation; and when turning down to its new place
of rest, that its descent should be so influenced by the form of the plough as
to make its full gradual, and in such a manner that it shall disturb as little
as possible the hinder part or tail of the plough. To attain this; proper forms
must be given to the coulter, the share, and the turn furrow or mould board.
To assist workmen in attaining these important points, I shall give such instruc-
tions as may tend to facilitate their labours, at the same time that they will
make them perfectly masters of those alterations or improvements in the whole,
or in the different parts, which constitute my said Invention. I shall begin
with the mould board, of which I make my share apart, in the general figure
which I am about to give directions for attaining. For illustration, suppose
the plough is wanted to turn over a furrow slice, ten inches broad, and five
inches deep. From the point A, Fig. 1, with a radius of ten inches, describe
the semicircle B, C, D. Let A, B, E, F, represent a horizontal section of the
furrow slice which is to be raised and turned over by the plough. As it is
made to rise from its natural horizontal position by the action of the plough,
it will turn on its angle A, the other lower angle B rising till the section attains
bigher positions, say A, G, H, I, and A, C, K, L, at the latter of which it is at
its highest elevation; and as it quits its perpendicular position to be turned
over, it will now turn on the point L, and in descending assume in succession
the positions L, M, N, O, and L, P, Q, R, at which last it may be sup-
posed to be in its place of rest. From an inspection of the Figure it will be
seen that no mould board conceived to be found out of a seme-cylinder,
of which the semicircle B, C, D, is a section, would present depth enough of
surface to turn the furrow slice over entire into its place after passing the perpen-
dicular, for the part a, N, of the furrow slice which falls beyond the radius A, a,
would have no part of the mould board acting upon it. It is therefore neces-
sary, in conceiving of such a solid as might contain in it a mould board of
sufficient breadth; that additional matter be added to the semi-cylinder.
get this addition from the point L on which the furrow slice turns with the
radius L, 6, describe the arc C, 6, Q, and the section with this addition will now
be that of a solid, which can comprehend the whole furrow slice in every part
of its change, from being cut till laid at rest. To compleat the curve without
a visible angle, take any new centre that will enable you to sweep the arch
G, B, and you have now obtained the form of a cross section (A, B, G, b, Q, A,)
To

page_text: of such a solid as would contain the required figure for a mould board. Let
S, T, U, X, Fig. 2, represent a solid, forty inches long, of which Fig. 1, before
described, is a section, and let the section of Fig. I be represented in Fig. 2 by
a, b, c, d, e, f, g, h, i, k. It is required that such a line be generated on the
uper surface of this solid as may answer for the upper edge of a mould board,
able to conduct the furrow slice gently, and with an easy curvature, to its
highest elevation, and then by a reversed gentle curvature to bring it over
to its place of rest. Of this I shall give a practical example, premising that a
competent workman may alter the proportions which I shall lay down, and
still gain a good line of curvature if he attends to the general principles of con-
struction. Divide the end of the solid into angles regulated by the degree of
curvature demanded, and all congregating at the point a-say, into the angles
b, a, c, of ten degrees; c, a, d, of fifteen degrees; d, a, c, of 20°; e, a, f, of 25;
f, a, g, of 25°; g, a, h, of 20°; h, a, i, of 15°; and i, a, k, of ten degrees.
Observe, of the first four angles amount to 70°, and the eight to twice
70° 140°, and that up to 70° the increments are increasing, and from 70° to
140 they are decreasing. Divide the line S, X, (which answers to the land
side of the plough) into eight equal parts (each of which, by the ease assumed,
will be equal to five inches) parallel to S, X; from the points c, d, e, f, g, h, i, k,
draw the lines c D, dE, e F, ġ H, hI, i K, and parallel to S, T, (that is,
at right angles to S, X,) draw the lines sr, tq, up, xo, y n, zm, and *1. Join
the points at which the latter parallel lines intersect the former by the
lines lm, mn, no, op, pq, qr, then join X e, and also T, and you obtain
an approximation to a returning curved line, which may be freed from the
angles which it presents by taking intermediate proportionals; but in practice
this is not necessary, as a workman's eye will enable him, in working, to free
this line from all asperities. The curved line thus obtained will represent the
upper edge of an efficient mould board, which will be found to answer
its purpose well if a proper form be given to the face of the mould board, the
formation of which shall next be described. Let A, S, X, L, represent a
rectangular horizontal plane, ten inches broad and forty inches long, measure
twenty-eight inches from A to B, and join B, X; and the plane A, S, X, B,
will represent the base or sole of my plough, X its point, and X, B, the cutting
edge of its mould board; that is, of the share attached to the mould board, and
which forms part of the figure or form which I am about to describe. The form
required for the face of the mould board will be obtained by ascertaining a
sufficient number of right lines, each of which (if the furrow slice had no
thickness) would commence in a different point of the edge A, B, of the
base A, B, X, S, and would terminate respectively in different points in the

page_text: curved line X, l, m, n, 'o, p, q, r, T; but as room must be left at the tail
of the plough to allow that part of it, A, C, T, which overhangs the base, to pass.
on without impediment as the furrow slice (say five inches thick) is turning.
over its place, the right lines for forming the hinder half of the face of the
mould board must take their departure from points higher than the base, but
must all terminate in the aforesaid curved line X, m, o, q, T. To make this
the more intelligible, recollect that, as shewn in its section in Figure 1, the
furrow slice after passing the perpendicular turns on the point L (Fig. 1),
and observe that in so passing the perpendicular its angle P describes.
the arc A, M, P, penetrating the limits of the solid Q, A, B, G, C, b, Q, and
therefore that part of the said solid which is bounded by the said arc A, M, P,.
and by P, Q, the upper side of the section of the furrow slice must be removed.
to allow the easy passage of the plough over the laid furrow slice. It is for,
this reason that in Fig. 2 the auxiliary lines 1 p, 2 i, and 3 K, all of which
are tangents to the arc a, 1, 2, 3, (or to A, M, P, of Fig. 1,) have been substi-
tuted for the lines a p, a i, a K, that were employed as auxiliries in attaining
the curved edge X, m, o, q, T, of the mould board. Let the edge A, B, of the
base be divided in the following proportions:-B, a, one inch; a, b, two inches;.
b, d, four inches; d, e, seven inches, together fourteen inches, or one half of
the whole line A, B; then divide the remaining half into four parts, e, f,
seven inches; f, g, four inches; g, h, two inches; and h; A, one inch.
Conceive a right line to pass from a to l, coinciding with the inclined
plane a, c, D, L; another right line to pass from 6 to m, coinciding with the
inclined plance a, d, E, L; another right line to pass from d to n, coinciding with
the inclined plane a, e, F, L; another right line to pass from e to o, coinciding
with the inclined plane a, f, G, L; another right line to pass from f to p,
coinciding with the inclined plane a, g, H, L; another right line to pass
from g to q, coinciding with the inclined plane 1 h, I 4, and another right line
to pass
from to r, coinciding with the inclined plane 2 i, K 5; then conceive
all that part of the aforesaid solid which lies to the furrow side, that is, to
the right of the lines B X, a 1, b m, d n, e o, fp, 9 q, ir, and k T, to be
removed, and you will obtain a twisting or winding curved surface approxi-
mating to the form which I give to the surface of the mould board of my
plough. I say approximating, because only a small number of lines have been
employed to gain this form, but between the said right lines any assignable
number of lines may be supposed to exist, or such a number as will exhibit
a surface free from sensible angles. To convey an idea of the production of
this surface mechanically: Let a workman form a piece of wood, forty inches
long, into the figure of which, a, b, c, d, e, f, g, h, i, k, 3, 2, 1, a, is a cross

page_text: section, the base a, b, being ten inches wide. With a saw cut off all the
wood that lies to the right of B, X; make a perpendicular cut in the line a, l,.
penetrating to the edge A, L, at a, and to the point l on the side S, X; and
the part of the solid that remains uncut between a, l, and the base, will be
represented by the triangle a, b, c; then clear away the wood from a, l, to
the cutting edge B, X; in like manner make another perpendicular saw cut
in the line b, m, penetrating to the edge A, L, at b, and to the point m on,
the side S, X, and the part of the solid that remains uncut between b, m, and.
the base will be represented by the triangle a, b, d; then clear away the wood-
from the bottom of the saw cut b, m, to the bottom of the preceding saw.
cut a, l. Proceed in the same manner at the succeeding lines dn, eo, fp, 99,
and ir, and the respective portions left uncut between the bottom of each
cut respectively and the base will be represented in succession by the
triangles a be, a bf, abg, abhi, a bi 2; remove the wood between saw.
cut and saw cut in succession, and lastly between K, T, and i, r, leaving the
solid matter between the bottom of the different cuts and the base entire, and
you will obtain the form of my mould board so nearly true that a workman's.
eye will enable him to remove all asperities. The share of my plough, as I
have already intimated, forms part of the figure of the mould board that has
been described, being fitted to the mould board in such a manner as to
preserve the required form (and fastened to it by the well-known means of bolts
or screws). The diagonal edge B, X, of the share cuts the earth in its whole
length, which embraces the entire breadth of the base of my plough, and in this
respect differs much in its action from other ploughs hitherto in use. I com-
monly attach the share to the place in the mould board, to which it is fitted by
two or more projecting pins, with each having a head at right angles to the pin:
see Fig. 3. The heads enter into holes of the same size in the mould board,
and the share being then moved in the direction X, B, being brought over.
solid parts of the mould board, serve as fastenings, as shewn in Fig. 4. The
share is kept from sliding back out of its place by the coulter, which is
attached to the land side of the plough. The coulter of my plough also
differs considerably in its form and position from others in use; it is a segment
of a circle, and occupies a space equal to its own thickness in the mould
board on its land side, the front extremity of the said segment of a circle
(which is about fifteen inches in diameter) coinciding with the point X of the
mould board and share, and the whole being fitted into a corresponding
circular cavity in the iron work on the land side of the plough, in such a
manner that it can be moved, when required, in the circular cavity as if
turned on a pivot; the use of this arrangement will be seen immediately:

page_text: The front extremity of the coulter has a projecting point, which by this
arrangement becomes part of the share, and is the first part that penetrates
the soil, and, being followed by the circular part, the earth is cut vertically
to the whole depth that the plough is to work, and at the same time close to
the lifting part of the plough; and, as every share wears away fastest on its
lowest side, and in time ceases to cut deep enough, my arrangement enables
me, by turning down the front extremity of my coulter (making it to revolve
a little in the proper direction), to bring the plough from time to time into
proper action till the whole of the said projecting point of the coulter is
successively worn away, instead of being obliged, as in common ploughs, to
send the share to the smith every time that it wants depth of cutting power.
Fig. 5 is a representation of my coulter viewed from the land side, move-
able in the semicircular grove a, b, c, d, and shewing how the point e may be
lowered, when necessary, to the position represented by the dotted point f.
I have yet another improvement to describe, which is peculiar to my
plough, whether used as a wheel plough or as a swing plough. I make my
beam moveable upon a pivot on the land side of the plough, situated nearly
perpendicular to o in Fig. 5, when used as a wheel plough, but the said pivot
is thrown forward a few inches (say four or five) for the purpose of lengthen-
ing the beam when used as a swing plough, and the beam is put upon a
pivot for the purpose of enabling the ploughman, without leaving his position
between the handles of the plough, to elevate or depress the plough to vary
the thickness of the slice, which he is enabled to effect by the following con-
trivance To the end of the beam next the handles (and which, in my
plough, I make to terminate where the handles are kept asunder by a piece
of iron) I fasten a piece of iron, descending almost vertically for about nine
inches, from the said end of the beam, and passing through a hole in the
aforesaid iron that keeps the handles asunder, or through an iron socket pro-
vided for the purpose, and which may be retained in any part of its vertical
depth, in the said hole, by means of a screw, or of any of the usual mechanical
contrivances for retaining a bar in its place. To speak more accurately, the
said vertical piece of iron forms a segment of a circle, of which the beam
from the aforesaid pivot is the radius; this being within reach of the plough-
man, he is enabled to elevate or depress the plough at pleasure. When the
plough is to be used as a wheel plough, I introduce between the beam and the
axis of the wheels a link or two of chain, with a swivel or any contrivance that
will act as an universal joint, thereby enabling the ploughman (as when
using a swing plough, as before described, to alter the position of the plough
upon any sudden emergency, and that without having occasion to stop to alter

page_text: any of the machinery. In describing my plough as above, I have mentioned
determined prepositions and angles for the sake of giving to the workmen
who may hereafter be employed to construct them a correct practical example,
but, from the description which I have given, any competent machinist will
not be at a loss to vary the proportions so as to alter the sweep of the mould
board or the angle of the diagonal edge of the share, as may be desirable
for the more stiff or loose mould of particular districts. I have further to
add, that though, for general purposes, I prefer the diagonal straight edge
which I have given to my mould board and share in the preceding description,
there are soils for which it may be desirable to provide shares possessing
other properties. I allude particularly to soils abounding with stones. For
fields of this description I would recommend, as an appendage to my plough,
that shares of the following form should be provided, to be substituted when
necessary, instead of the share above described.
Fig. 6 is such a share as I have alluded to as a substitute; it is in fact
the same share that I have already described, but having the straight edge
indented with curves, and all brought to an edge; the projecting points
facilitating the progress of the plough through stoney soils.
In witness whereof, the said William Cooke hath hereunto set his
hand and seal, the Fourteenth day of August, in the fifty-third year
of the reign of King George the Third, and in the year of our Lord
One thousand eight hundred and thirteen.
AND BE IT REMEMBERED, that on the same Fourteenth day of August,
in the year above mentioned, the aforesaid William Cooke 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.
Inrolled the same Fourteenth day of August, in the year above written.