IMPROVE- MENTS IN THE CONSTRUCTION OF ARTIFICIAL LEGS AND FEET
Year: 1858

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, and of 166, Buchanan Street, in the City
of Glasgow, North Britain, Gentleman, for the Invention of "IMPROVE-
MENTS IN THE CONSTRUCTION OF ARTIFICIAL LEGS AND FEET."-A coni-
munication from Douglas Bly, of Rochester, in the United States of
America.
Sealed the 16th November 1858, and dated the 17th May 1858.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on the
17th May 1858.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF ARTIFICIAL LEGS AND FEET," a com-
munication from Douglas Bly, of Rochester, in the United States of America,
to be as follows:-
This Invention relates to a peculiar construction and arrangement of
artificial legs and feet, whereby their actions are made to assimilate nearer
to those of the natural linib than has hitherto been effected. According to
this Invention a lateral and diagonal fluxion of the foot at the ankle joint is
provided for, as well as the ordinary forward fluxion. This is accomplished
by connecting the foot to the leg by means of two sets of cords and springs

page_text: in combination with a universal or ball-and-socket joint; these two sets of
cords and springs operate antagonistically to each other, one set being placed
on each side of the ball-and-socket joint; hence it is obvious that a perfectly
universal fluxion of the foot is obtained in any direction. The springs used
serve as muscles, and are made of india-rubber tubes, whilst the cords scrvo
as sinews, and are so connected to the springs as to be capable of adjustment
by nuts and screws, so that their tension may be regulated with the greatest
nicety. Cords and india-rubber springs are also employed for connecting the
toe or point of the foot to the body, so as to allow of free play at that part
when required.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Jolinson; in the Great, Seal Patent Office on
the 16th November 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, 'JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
and of 166, Buchanan Street, in the City of Glasgow, North Britain, Gentle-
man, send greeting.
WHEREAS Her most Excellent Majesty, Queen Victoria; by; Her, Letters
Patent, bearing date the Seventeenth day of May, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Henry Johnson, Her special license that I, the said John
Henry Johnson, my executors, administrators, and assigns, or such others as
I, the said John Henry Johnson, 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 terni 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 "IMPROVE-
MENTS IN THE CONSTRUCTION OF ARTIFICIAL LEGS AND FEET," (a communication
from Douglas Bly, of Rochester, in the United States of America,). upon the
condition (amongst others) that 1, the said John Honry Johnson, 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.

page_text: NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings, and
to the letters and figures marked thereon, that is to say:-
The said Invention relates to a peculiar construction and arrangement of
artificial legs and feet, whereby their actions are made to assimilate nearer to
those of the natural limb than has hitherto been accomplished. According
to this Invention a lateral and diagonal flexion of the foot at the ankle joint is
provided for, as well as the ordinary forward flexion. This is accomplished by
connecting the foot to the leg by means of two sets of cords and springs, in
combination with a universal or ball-and-socket joint. These two sets of cords
and springs operate antagonistically to each other, one set being placed on
each side of the ball-and-socket joint; hence, it is obvious that a perfectly
universal flexion of the foot is obtained in any direction. The springs used
serve as muscles, and are made of india-rubber tubes, whilst the cords serve
as sinews, and are so connected to the springs as to be capable of adjustment
by nuts and screws, so that their tension may be regulated with the greatest
nicety. Cords and india-rubber springs are also employed for connecting the
toe or point of the foot to the body, so as to allow of free play at that part
when required.
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose I shall
refer to the several Figures on the Sheet of Drawings hereunto annexed, the
sanie letters of reference indicating corresponding parts throughout all the
Figures.
Figure 1 of the annexed Sheet of Drawings represents a side elevation of
an artificial leg constructed according to this Invention; Figure 2 is a vertical
section of the same, taken in the direction of the length of the foot; and
Figure 3 is a vertical section, taken at right angles to Figure 2.
A, A', are the two sets of antagonistic cords and springs. The springs a, a',
may be composed of short lengths of vulcanized india-rubber, and serve the
purpose of the muscles of the human leg, whilst the cords b, b', answer the
purpose of the tendons. These cords and springs are secured by nuts c, c,
which afford facility also for adjusting their tension, and are disposed in two
sets, one set on each side of the universal joint B, which is composed of a ball
fitting between corresponding cavities formed in the foot and leg, so that the
combination of the whole will afford facility for bending or turning the leg
the foot in a lateral and diagonal, as well as in a forward and backward
upon

page_text: direction; and as the foot is connected with the leg by the intervention of a
ball-and-socket joint,. it follows that the foot can be moved or flexed in any
direction around the whole circle, which is a very great advantage in many
cases, as, for example, in walking or standing on sidelong ground, such as the
side of a steep bill, or when accidentally treading upon a stone or other
obstacle or irregularity of surface likely to twist the foot laterally or diagonally,
or when one leg is required to be placed at some distance apart from the other,
in all which cases the power of lateral and diagonal flexure of the leg upon
the foot will be found highly advantageous. I do not confine myself to any
particular form of or mode of attaching the springs, cords, and ball joint, so
long as the combination is such that the several springs and cords, or artificial
muscles and tendons, will act antagonistically to each other on opposite sides
of the joint, and permit of a lateral and diagonal play or action thereof.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as variations may be made therefrom without deviating
from the principles or main features of the said Invention; but what I con-
sider to be 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 providing for the lateral and diagonal flexion
of the foot on artificial legs, substantially in the manner herein-before
described.
Second, the combination in artificial legs and feet of side cords and
springs, with a spherical joint or its equivalent, for the purpose herein-before
referred to.
In witness whereof, I, the said John Henry Johnson, havo hereunto set
my hand and scal, this Fifteenth day of November, One thousand
eight hundred and fifty-eight.
J. HENRY JOHNSON. (L.S.)