A NEW OR IMPROVED INSTRU- MENT TO BE USED IN CASES OF DIFFICULT PARTURITION.
Year: 1866

page_text: LETTERS PATENT to George Robert Sheraton, of Sedgefield, in the
County of Durham, for the Invention of "A NEW OR IMPROVED INSTRU-
MENT TO BE USED IN CASES OF DIFFICULT PARTURITION.
PROVISIONAL SPECIFICATION left by the said George Robert Sheraton
at the Office of the Commissioners of Patents, with his Petition, on
the 3rd July 1866.
I, GEORGE ROBERT SHERATON, of Sedgefield, in the County of Durham, do
hereby declare the nature of the said Invention for "A NEW OR IMPROVED
INSTRUMENT TO BE USED IN CASES OF DIFFICULT PARTURITION," to be as
follows:-
This Invention consists (as represented in Fig. 1) of two blades of flexible
steel curved in a somewhat sigmoid form. These blades are united at one
extremity by a moveable linked joint, and at their other extremities are fitted
into the rotary bars, which allows each blade to rotate in opposite directions
to the extent of 90°, forming a hoop as, B, Fig. 1, or to be placed parallel to

page_text: each other, as A, Fig. 1. The power of rotation is obtained by pressing upon
the transverse bars or "lugs" of the rotary bars, as D, Fig. 1, which rotates
upon the handle by which the requisite angle is obtained. The degree of
rotation is limited by stops or pins E, Fig. 1, in the handle, and by the form
of the linked joint c and rotary bar. The handle is flattened on one side to
enable the operator to determine with accuracy the degree of angle obtained,
and its relative position with respect to the foetal head and maternal passages
as in F ("in Fig.:1").
The blades, Fig. 2, a consists of two strips of rolled, drawn, or hammered
steel of from 9 to 12 inches in length, of about tbs inch in width, and of
At one extremity the two
from No. 17 to Ne:.22 (wire guage.) in thickness.
blades are connected with the linked joint (c) by being rounded at their
extremities, and perforated with a hole (c) of th inch diameter, corres-
ponding with two holes of the same size in the link through which two pins
are fitted and rivetted. The lower extremity of each blade fit into a slit in
the rotary bar (d), where they are fixed by: two small pins passing through
each of them. Each blade is curved in a sigmoid form a (Fig. 1), the amount of
curvature forming an ellipse, having a short diameter of about 5 or 6 inches.
The blades are tempered so as to be Bexible, elastic, and tenaceous in the
highest degree. The blades may be electroplated with silver or gold, or
covered with gutta percha, caoutchouc, or other substance if thought desirable.
The linked joint c (Fig. 2) forms-the point of the instrument when the blades
are parallel, and connects the two blades as to form a hoop when open. It
consists of a piece of steel th inch in width, th inch in length, and
nds inch in thickness, and this thickness is split to ths inch of its
length to admit the two blades of the instrument, the remaining tbs
which forms the point -being solid, and which also serves the purpose of a
stop by limiting the extent of rotation of each blade to 90°. Two holes c
(Fig. 2) th inch diameter slightly countersunk to admit the rivets which
connect the link with the blades. The anterior or solid portion is rounded,
forming the arc of a circle of 1 inches diameter, and the posterior portion is
rounded by two-circles drawn from the rivet boles. The rotary bars d.(Fig. 2)
are two bars of steel or iron-of irregular form, into which the lower extremities
of the blades are fixed. It passes through the handle upon which it rotates,
and is retained in its position by nuts being screwed upon the ends. The
portion into which the blades are fixed are ths inch in width and incl
in thickness, with the edges bevelled off, and split for about inch of their
length, into which the lower ends of the blades are fitted and fixed by two
small pins passing through each of them, as d (Fig. 2). Immediately below

page_text: this for ths of its length (d) it is th inch diameter, and rounded on.
three-fourths of its circumference, and left square on the remaining one-fourth,
which is the posterior or outer part; this allows them to rotate till the two
A
square surfaces come in contact, thus limiting the degree of rotation.
transverse bar or "lug" (d) about th inch in length, inch broad
on its upper surface, and reduced to th inch on its under surface,. projects
from the outer side of each of the rotary bars for the purpose of opening the
blades on application, and by which the force is applied in extraction by the
fingers. being laid across them. A bar (3) 3 inches in length, th inch
diameter, which passes through the handle upon their lower ends, is cut to
allow nuts to be screwed upon them for the purpose of retaining them-in. their
position at (d). (Fig. 2). The nuts e (Fig. 2) are two. in number,. and are
screwed upon the ends of the rotary. bars; they are of conical form so- to fit
into the end of the handle,. which is countersunk to receive them ; they are
notched at the end transversely for the key to fix or remove them (e', Fig. 2).
The handle (Fig. 2) consists of two-parts; f¹ (Fig. 2) is of steel, irou, or
brass, and consists of a longitudinal piece about 3 inches in length,
breadth, and th inch in thickness, and of two ends or transverse portions;
also th inch in thickness, inch broad in its antero-posterior diameter,
and about one inch in their transverse diameter. Each end is perforated
with two holes th inch diameter, through which the lower portion. of the
rotary bars pass, the holes in the lower end f³ (Fig. 2) being countersunk
to admit the nuts which are screwed upon the ends of the bars. The
portion marked (f2, Fig. 2) is of ebony or other hard-wood, ivory, or bone;
so shaped as to fit and fill up the space in the iron portion f¹ (Fig. 2).of
the bandle, and retained there with pins. passing through and rivetted; it is
rounded on its anterior two-thirds, the posterior third being flattened, thus
forming the handle about 3 inches in length, inch its antero-posterior
diameter, and 1 inch in its transverse diameter and 1. inch in its transverse
diameter (as in Fig. 2; f*)..
in
It is not necessary that the above measurements should be strictly adhered
to, but is the size that the instrument is intended to be made. The instrument
may be made with a folding joint (as in Fig. 3, A, B,) to render it

page_text: SPECIFICATION filed in pursuance of the conditions of the Letters
Patent, and of an Order of the Lord Chancellor, by the said George
Robert Sheraton in the Great Seal Patent Office on the 18th January
1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
ROBERT SHERATON, of Sedgefield, in the County of Durham, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of July, in the year of our Lord
One thousand eight hundred and sixty-six, in the thirtieth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said George Robert Sheraton, Her special licence that I, the said
George Robert Sheraton, my executors, administrators, and assigns, or such
others as I, the said George Robert Sheraton, 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 "AN IMPROVED INSTRUMENT TO BE
USED IN CASES OF DIFFICULT PARTURITION," upon the condition (amongst
others) that I, the said George Robert Sheraton, my executors or admini-
strators, 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 George Robert Sheraton, 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 :-
My Invention consists, as represented in Drawings, of two blades of steel
curved in a somewhat sigmoid form. These blades are united at one
extremity by a moveable linked joint, and at their other extremities are fitted
into the rotary bars, which allows each blade to rotate in opposite directions
to the extent of 90°, forming a hoop, as B, or to be placed parallel to each
other, as A. The power of rotation is obtained by pressing upon the
transverse bars or "lugs" of the rotary bars, as D, which rotates upon the

page_text: handle, by which the requisite angle is obtained. The degree of rotation is
limited by stops or pins E in the handle, and by the form of the linked
joint C.
The bandle is flattened on one side to enable the operator to
determine with accuracy the degree of angle obtained and its relative position
with respect to the foetal head and maternal passages, as in F. The blades
A, B, consists of two strips of rolled, drawn, or hammered steel of from 8 to
12 inches in length, of about 7ths inch in width, and of from No. 17 to
No. 22 (wire guage) in thickness. At one extremity the two blades are
connected with the linked joint (C) by being rounded at their extremities
and perforated with a hole (Ca) of th inch diameter corresponding with
two holes of the same size in the link, through which two pius are fitted and
rivetted. The lower extremity of each blade fits into a slit in the rotary bar
(G), where they are fixed by two small pins passing through each of them.
Each blade is curved in a sigmoid form (A & B) the amount of curvature
forming an ellipse, having a short diameter of from 3 to 4 inch, and a long
diameter of about 5 or 6 inch. The blades are tempered so as to be flexible,
elastic, and tenacious in the highest degree, or as in Aa and Bb, and the blades
may be of th inch in thickness, gradually increasing downwards to about
inch, or th inch, and of about 1 or 1 inch width at the upper part,
decreasing downwards to about inch, the edges being rounded off; they
may be fenestrated, as I, to render them lighter. The upper part or point of
the blades are to be rounded off, as H, and the blades are rigid, and therefore
do not require to be connected at the upper part with the linked joint, and
the blade and rotary bar may be forged in one piece. The linked joint (C)
forms the point of the instrument when the blades are parallel, and connects
the two blades as to form a hoop when open; it consists of a piece of steel
ths inch in width, gths inch in length, and nds inch in thickness, and this
thickness is split to ths inch of its length to admit the two blades of the
instrument, the remaining feths, which forms the point, being solid, and
which also serves the purpose of a stop by limiting the extent of rotation of
each blade to 90°. Two holes (Ca), th inch diameter, slightly countersunk
to admit the rivets which connects the link with the blades. The anterior
or solid portion is rounded, forming the arc of a circle of 1 inch diameter,
and the posterior portion is rounded by two circles drawn from the rivet holes;
or this linked joint may be, dispensed with, as in Aa, and Bb. The rotary
bars (G and D) are two bars of steel or iron, brass or other metal of irregular
form, into which the lower extremities of the blades are fixed. It passes
through the handle, upon which it rotates, and is retained in its position by
nuts being screwed upon the ends. The portions into which the blades are

page_text: fixed are ths inch in width and inch in thickness, with the edges bevelled
off and split for about inch of their length, into which the lower ends of the
blades are fitted and fixed by two small pins passing through each, as G.
The degree of rotation is limited by pins or stops upon the upper end of the
handle, limiting the degree of rotation to 90%, as E. A transverse bar or
Ing D about ths inch in length, inch broad on its upper surface and
reduced to th inch on its under surface projects from the outer side of each
of the rotary bars for the purpose of opening the blades on application, and
by which the force is applied in extraction by the fingers being laid across
them. Bar K 3 or 4 inches in length, ths to inch diameter, which
passes through the handle upon their lower ends a thread is cut to allow nuts to
be screwed upon them for the purpose of retaining them in their position,
at L. The nuts M are two in number, and are screwed upon the ends of the
rotary bars; they are of conical form so as to fit into the end of the handle,
which is countersunk to receive them; they are notched at the end
transversely for the key to fix or remove them, or the bars may be retained
in the handle by pins passing through them. The handle N consists of two
parts; O is of steel, iron, brass, or other metal, and consists of a longitudinal
piece or about 3 or 4 inches in length, to 1 incli in breadth, and th inch
in thickness, and of two ends or transverse portions also th inch in thickness,
inch broad antero-posteriorly, and about 1 to 1 inch in their transverse
diameter; each end is perforated with two holes th to inch diameter,
through which the lower portion of the rotary bars pass, the holes in the
lower end being countersunk to admit the nuts which are screwed upon the
ends of the bars. The portion marked P is of ebony or other hard wood,
ivory, or bone, so shaped as to fit and fill up the space in the iron portion O
of the handle, and retained there with pins passing through and rivetted. It
is rounded on its anterior two-thirds, the posterior third being flattened, thus
forming the handle about 3 or 4 inches in length, or 1 inch in its antero-
posterior diameter (that is, from before backwards), and 1 or 1 inch in its
transverse diameter, as in N. Or the handle may be made of two lateral
halves by being divided longitudinally and connected with a hinged joint
which permits them to be separated at will to increase the transverse diameter
of the ellipse formed by the blades, as in Q. A screw R may be made to
pass through the handle to limit the amount of separation of the two halves
of the handle by the screw having a pitch of about one complete turn in every
to inch with a cog nut which readily runs upon it, but which may be
arrested as required by a detent with spring. A key T may be used where
great pressure is needed to act upon the screw.
A toothed rack S upon a

page_text: spring passes through the handle having the teeth cut saw-shaped as to permit
the two halves of the handle being closed, but prevents their separation, thus
acting as a detent. The metallic portions of the instrument may be electro-
plated with silver, gold, or the blades covered with caoutchouc or other substance
if thought necessary.
It is not necessary that the above measurements be strictly adhered to,
but is the size that it is intended to be made.
In witness whereof, I, the said George Robert Sheraton, have hereunto
set my hand and seal, this Fifteenth day of January, in the year
of our Lord One thousand eight hundred and sixty-seven.
GEORGE ROBERT SHERATON. (L.S.)