IMPROVEMENTS IN APPARATUS FOR TILLING LAND
Year: 1863

page_text: LETTERS PATENT to Charles Harratt, of Hornsey Lane, Highgate, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN APPARATUS
FOR TILLING LAND."
Sealed the 4th December 1864, and dated the 28th August 1863.
PROVISIONAL SPECIFICATION left by the said Charles Harratt at the
Office of the Commissioners of Patents, with his Petition, on the 28th
August 1863.
I, CHARLES HARRATT, of Hornsey Lane, Highgate, in the County of
Middlesex, do hereby declare the nature of the Invention for "IMPROVEMENTS
IN APPARATUS FOR TILLING LAND," to be as follows:-
This Invention has for its object improvements in apparatus for tilling land.
The apparatus, as is shown in the Drawings hereunto annexed, is composed
of an axis c, carried in bearings in a suitable frame, the frame is provided
with wheels to run along the land; these wheels are not shown in the
Drawings; from two opposite sides of the axis two arms a, a, project; these
arms carry blades of bar iron b, b, which together form a harrow, spaces.
being left between the bars as is shown. The arms also carry spades
A, A, A, B, B; B. "When the apparatus is drawn along the land, and the
axis c caused to revolve, the blades or bars 6 first act on the ground, and
drive before them narrow slices of earth, which are at intervals apart from
each other, the spades which are in the position of those marked A in the

page_text: Drawing, then come into action and cut away the parts left between the slices
of earth removed by the blades b, and carry the whole over to the position of
the spades marked B, when the earth falls and breaks into pieces; in the
meantime the spades B will have come into action, and the same operation
will be repeated on a fresh piece of land as the apparatus will have moved
forward a suitable distance to enable it to do so. The outer curved surface of
the spade is made eccentric to admit of the apparatus moving forward.
By combining apparatus for sowing seed, with an apparatus such as is
above described, the land may be ploughed, sown, and harrowed, at one
operation, the machine being moved but once over the ground.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Harratt, in the Great Seal Patent Office on the
27th February 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, J, CHARLES
HARRATT, of Hornsey Lane, Highgate, in the County of Middlesex,. send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of August, in the year of our
Lord One thousand eight hundred and sixty-three, in the twenty-seventh
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Charles Harratt, Her special licence that I, the
said Charles Harratt, my executors, administrators, and assigns, or such others
as I, the said Charles Harratt, my executors, administrators, and 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 Inven-
tion for "IMPROVEMENTS IN APPARATUS FOR TILLING LAND," upon the condition
(amongst others) that I, the said Charles Harratt, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their hands
and seals, 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 Charles Harratt, do hereby declare the
nature of the said Invention, and in what manner the same is to be

page_text: performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the accompanying Drawings,
and to the letters and figures marked thereon, that is to say :-
Figure 1 is a side view, and 2 a plan of parts of a machine con-
structed according to my Invention. The spades s are made to rotate
round an axle (a), in the direction of the arrow by two pairs of drums and
chains of equal diameter shewn in the Figures; one pair of drums is fixed
upon an axle (6), beside the hind wheels which are also keyed to the same
axle, as also are two holdfasts which hold one way and slip the other like a
friction brace. From these holdfasts rise upwards two levers, the longer (c)
for the hand power, the shorter (d) for the steam power which acts upon it by
the piston rod. The two levers are connected by two small drums and a
chain (not shewn), which serve also to reverse their motion, so that if the
short lever is pulled by the piston from (e) to (f), forcing round the hind
wheels, the longer lever slips backwards from (e¹) to (f), and vice versa.
Eight spades are shewn, but there may be as many as the width of the
machine admits of following each other at equal intervals; from the lower
edge of the spades project several cutters (1), which drive before them slices
of earth, and these slices are again cut transversely by several bolts of iron (2)
which pass through the cutters (1), and other bolts or narrow spades (3), the
earth dug out by each spade is dropped when it comes round to the after side.
When moving along the ground, but not in work, the spades are raised by a
small winch (not shewn) on each side of the machine, which draw up the
axle (a) along two strong pillars (4) forming part of the frame, which are
curved on the after side to a radius equal to the distance between the centres
of the two axles.
Figure 3 shews a side view of one of the holdfasts to a larger scale, which
is keyed on to the axle (b); it is a circular piece of iron with a projecting rim
on each side, which fits into a brass key on each side. The whole being
turned to fit exactly between the two brass keys rises upwards the lever (c),
its lower end rests upon the external surface of the holdfast, which it is turned
to fit, and in this position it is firmly held by two bolts which pass through it,
and the two brass keys. Now, when the lever is moved in the direction from
E to G, the brass keys slide closely upon the inner side of the rim, which
prevents any grip at the points E and D, and the lever slips, but when it is
moved in the direction from G to E the brass keys recede from the inner side
of the rim, and admit of a grip at E and D, which carries round the holdfast
in that direction, and with it the hind wheels and chain wheels, whereby
motion is communicated by the chains to the axis of the spades. The angle

page_text: E, C, D, should be 45°, the angle E, D, C, 90°; these conditions determine
the relative thickness of the rim E, g, and the breadth of the lever E, G.
Upon the upper end of the lever is fixed a cross head, which works in a slot
in the piston rod, or in a clutch extending beyond the end of it, and firmly
attached to it. The plan of the clutch, Figure 4, shews the upper edges
P. p', q, q', of four vertical faces, all of which in turn come into contact
with the cross head; the piston is shewn at half stroke; the face P is in
contact at o, having forced the cross head from (P) to o; the face p is also
for a moment in contact with the cross head above (P), and at the end of the
stroke will have forced it likewise from (P) to (o); the action is précisely
similar on the return of the piston, putting q, q', for p, p, thus the effort of
the piston is always exerted in an ascending arc on either side. There can be
no contact in the descending arc, because the sine of a circular arc is greatest
at the origin; for example, the sine of 1' is =000291; but the sine
(30°-1 -30°) is (*500252-5)=000252'r; therefore p will recede
from
P, p,
-
faster than p approaches to it. The curved surfaces of which
q, q', are the upper edges, and o, p, =ò, q, the sidė edges must be
such as will roll without rubbing along the vertical faces of the piston rod or
clutch. Such a curve' must fulfil three conditions. (First), its length must
be equal to the length of the ver. sine of the circular arc O, P. (Second), it
must have the same trigonometrical tangent. (Third), its normal must have
the same direction. The second and third will be fulfilled if the curve be
upon the cross head, but if it be made to change places (in the descending
arc) with the half face of the piston rod or clutch, the two first conditions
might be fulfilled, but not the third, for the direction of the normal would vary
with the inclination of the lever, hence the effort of the piston must be made
to act in an ascending are only. There may be two or more steps in the
ascending arc (o, p,) as before described, whereby its length is diminished, and
large arcs in O, P, may be traversed, thus a parallel motion may be reversed
without any friction. The curve (o, p,) is formed by the intersection of a
series of circles of varying radii, whose centres are in a line passing through (o)
at right angles with (C, O).
Points in the curve may easily be found. Put r for the radius of the circle
of curvature at any point (p), and (6) for the angle of inclination of the
2" ver. sine 8
lever, then r = a ver. sine 4 or
a constant throughout the
0
a
quadrant a few points are given below, and the form of the curve is shewn in
(Figure 5).

page_text: ver sines in (0,p).
Sines in (O, p).
. v. sine =0019 inch (a v. sine
g).
"
"
sine 6). v. sil
At 5°
a v. sine
10°
15°
20°
25°
30°
"
"
"
"
"
='0058
054.
"
3
sine 60458 inch
"
=1813
= 4036
33
"
='
39
124
"
-7124
33
33
=242
405
"
"
=1.09
"
"
"
=1.524
"
"
This table is made out on the supposition that (a) = 1 foot = the length
of a vertical line from C to a line passing through the centre of the piston rod.
With respect to the engine, the valves are opened and shut by a tumbler,
or by the hand power lever; they should be so placed that a small cushion of
steam be left at the ends if my Patent engine be used in which the chimney
is a hollow piston and piston rod; the stuffing boxes should be metallic at
both ends, and covered from dust or smoke.
In witness whereof, I, the said Charles Harratt, have hereunto set my
hand and seal, this Twenty-seventh day of February, in the year of our
Lord One thousand eight hundred and sixty-four.
CHARLES HAKKATT. (L.S.)