IMPROVEMENTS IN APPARATUS FOR DIGGING POTATOES
Year: 1868

page_text: LETTERS PATENT to John Wallace, of Glasgow, in the County of
Lanark, North Britain, Agricultural Implement Maker, for the
Invention of "IMPROVEMENTS IN APPARATUS FOR DIGGING POTATOES."
Invention of "IMPROVEMENTS IN Apparatus for Digging Potatoes.”
POTATOES."
Sealed the 2nd October 1868, and dated the 3rd April 1868.
PROVISIONAL SPECIFICATION left by the said John Wallace at the
Office of the Commissioners of Patents, with his Petition, on the
3rd April 1868. ...
I, JOHN WALLACE, of Glasgow, in the County of Lanark, North
Britain, Agricultural Implement Maker, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN APPARATUS FOR DIGGING
POTATOES," to be as follows; that is to say:
This Invention relates to improved apparatus for digging potatoes,
and consists in constructing it with grapes or rakes fixed to endless
chains and actuated from the carrying wheels so as to throw the
potatoes in a backward direction as the apparatus moves forward. Two
coulters fixed to the front of the framing make two vertical cuts, one

page_text: on each side of the drill of potatoes; and a grating with a shovel-
like forward end is fixed to the framing so as to enter under the
potatoes a little in advance of the grapes, whilst the points of the
grapes enter between the bars of the grating and carry the potatoes
backwards over it. The endless chains to which the grapes are attached
are passed round pitch pulleys on two transverse horizontal shafts
carried one towards the front and the other towards the back end
of the framing, and one of the shafts is driven by means of a pinion
on it which is in gear with an internally toothed ring fixed on the
spokes of one of the carrying wheels; or, if preferred, there may be
two pinions on the pulley shaft and toothed rings on both wheels to
gear therewith.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Wallace in the Great Seal Patent Office
on the 3rd October 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
WALLACE, of Glasgow, in the County of Lanark, North Britain,
Agricultural Implement Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of April, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did for Herself, Her heirs and successors,
give and grant unto me, the said John Wallace, Her special licence
that I, the said John Wallace, my executors, administrators, and
assigns, or such others as I, the said John Wallace, 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 Invention for "IMPROVEMENTS IN
APPARATUS FOR DIGGING POTATOES," upon the condition (amongst others)
that I, the said John Wallace, my executors or administrators; 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

page_text: 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 Wallace, 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 in writing, reference being had to the accom-
panying Drawings, that is to say:--
:
My said Invention relates to improved apparatus for digging potatoes
and consists in constructing it with grapes or rakes fixed to endless
chains and actuated from the carrying wheels so as to throw the
potatoes in a backward direction as the apparatus moves forward.
And in order that my said Invention and the manner of performing
the same may be properly understood I have hereunto appended a
Sheet of explanatory Drawings to be herein-after referred to and
representing a potato digging machine as constructed according to
my Invention.
Figure 1 is a sectional side elevation, and Figure 2 is a sectional plan
of the machine. The framing of the machine is in a rectangular form in
plan and consists of longitudinal iron bars 1 connected by cross bars 2.
The frame is carried on the axle 3 of two wheels 4, the tires of which
are fitted with spikes to enter the ground and ensure the rotation of
the wheels when the machine is drawn along by two horses. The
front end of the frame is supported by a pair of wheels 5 arranged
to swivel and connected to the end of a long lever 6 jointed to the
frame bars 1 by means of which lever 6 the operating parts can be
adjusted in position. Two coulters 7 provided with mould boards are
fixed to the front end of the frame and make two vertical or nearly
vertical cuts one on each side of the drill of potatoes. The grapes
or rakes 8 are arranged to enter the drill just behind the coulters 7.
These rakes consist of horizontal bars fitted with projecting prongs,
and fixed on two endless chains 9 and the chains pass round two
pairs of pulleys 10, 11, fixed on shafts carried in bearings attached
to the frame bars 1. On the ends of the shaft of one pair 11 of the
chain pulleys there are set with engaging and disengaging clutches
pinions 12, which gear with internally toothed rings 13 fixed on the
spokes of the wheels 4. With these arrangements on the machine
being drawn forward the endless chain 9 with the grapes or rakes 8

page_text: will be made to travel horizontally backwards along the under side
and the grapes will throw out the potatoes. A grating 14 with a
shovel-like forward end 15 is fixed to the framing by means of a
bent bar 16, and enters into the drill under the potatoes near where
the grapes begin to act. This grating 14 is slightly inclined, being
higher at its back end, and the grape points which just pass over the
shovel shaped front 15 afterwards enter between the longitudinal bars
composing the grating and carry the potatoes backwards up the incline
and to a considerable extent clear of the earth. When the apparatus
is in action the parts are adjusted as delineated, and the wheels 4, 5,
run in the furrows between the drills, the ordinary height of which
last is indicated by the dotted line 17-17. Instead of the grapes 8
being fixed to endless chains as described they may be attached to
a wheel of large diameter but I prefer the arrangement described,
as the movement of the grapes in a horizontal line is continued longer
and acts in a better manner on the potatoes.
Having thus particularly described my said Invention and the manner
in which the same is to be performed, I have to state that I do not
restrict myself to the precise details herein described or delineated,
but that what I believe to be novel and original and claim as the
Invention secured to me by the herein-before in part recited Letters
Patent is, the applying of a series of grapes or rakes for digging
potatoes, such grapes or rakes being actuated by endless chains or in
an equivalent manner, substantially as herein-before described.
In witness whereof, I, the said John Wallace, have hereunto set
my hand and seal, this Thirtieth day of September, in the year
of our Lord One thousand eight hundred and sixty-eight.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JOHN WALLACE. (L.S.)