IMPROVEMENTS IN THE CONSTRUCTION OF CASTORS
Year: 1855

page_text: LETTERS PATENT to John Kidder, of Plaistow, in the County of Essex,
Gentleman, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF
CASTORS."
Sealed the 22nd June 1855, and dated the 14th March 1855.
PROVISIONAL SPECIFICATION left by the said John Kidder at the
Office of the Commissioners of Patents, with his Petition, on the
14th March 1855.
I, JOHN KIDDER, of Plaistow, in the County of Essex, Gentleman, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
CONSTRUCTION OF CASTORS" to be as follows:-
This Invention relates to what are usually termed "ball castors," and
consists in a certain novel mode of constructing the case or socket which is
to retain the revolving ball in its place.
I form the inside of the said socket or case by turning or otherwise with
a flat internal surface at the top which rests on the revolving ball. I also
form the inside of the said socket rather larger than the ball, which in
revolving touches it on the side opposite to its direction of motion and at a
height which I prefer being about one-fourth of the diameter from the top
of the ball. The ball may be prevented from leaving the socket by bending
in extensions of the outer case or socket, or by a ring below the horizontal
diameter of the ball, which are generally not to touch it when revolving.

page_text: SPECIFICATION in pursuance, of the conditions of the Letters Patent, filed
by the said John Kidder in the Great Seal Patent Office on the
11th September 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
KIDDER, of Plaistow, in the County of Essex, Gentleman, send greeting.
WHEREAS IIer most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of March, in the year of our Lord
One thousand cight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said John Kidder, Her special licence that I, the said John Kidder, my
executors, administrators, and assigns, or such others as I, the said John
Kidder, 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
THE CONSTRUCTION OF CASTORS," upon the condition, (amongst others) that I,
the said John Kidder, 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 Kidder, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being bad to the Drawing hereunto annexed, and to the
letters and figures marked thereon. (that is to say) :-
My Invention relates to a novel mode of constructing the outer case or
carriage of what are usually termed "ball or socket castors," the said case
or socket being formed by turning, casting, or otherwise, with a flat internal
surface at the top which rests on the revolving ball. I also make the socket
larger than the ball, which in revolving touches only on the side opposite to
the direction in which it is travelling and at the top. The ball may be
prevented from leaving the socket by any suitable means.
In order that my Invention may be more fully understood, I have shewn in
the accompanying Drawing, at Fig. 1 a partial section, at Fig. 2 an elevation,
and at Fig. 2a sectional plan, taken in the line-1, 2, of Fig. 1, of my improved
ball and socket castor. a represents the ball, which may be made of any

page_text: suitable material; b is the case or socket shaped internally so as to present a
flat surface c to the top of the ball, the sides being either flat or curved, in
such a manner as to touch the ball at any part of the circumference of the
line d, e; the distance which I prefer is about one-fourth of its diameter from
the top, but it may be varied.
As the socket is made larger than the ball, when the castor is put in motion
the ball rolls towards the side opposite the direction in which it is travelling;
that is to say, supposing the castor to be moving in the direction of the arrow,
the ball will leave the side e, and touch only at the point d of the circumference
and roof c; on the contrary, when the castor is moved in the opposite direction,
it will leave the point d of the circumference, and touch at the opposite point e
and roof c, and so on in whatever direction it may be moved; the ball can
touch the case or socket only at two points, one at the top or apex of the ball,
the other at the side; the ball is prevented from leaving the socket by the
points f, ff, being turned in sufficiently to keep the ball from falling out, but
in such a manner as not to touch it when in motion, or by springing in a ring
in the ordinary manner.
Fig. 3 is a partial section, and Fig. 4 an elevation, of a modification of my
improved castor as adapted for securing to a flat surface.
The above-described castors are applicable to articles of furniture, gun
carriages, and other similar purposes.
Having now described and set forth the nature of my Invention for
"Improvements in the Construction of Castors," I wish it to be understood
that under the above in part recited Letters Patent I claim, the improved
arrangement of ball and socket castor, substantially as herein described and
represented.
In witness whereof, I, the said John Kidder, have hereunto set my hand
and seal, this Tenth day of September, in the year of our Lord One
thousand eight hundred and fifty-five.
JNO KIDDER. (L.B.)
Witness,
THO' RAINES,
.
24, Great Ormond Street, Queen Square.