Improvements in or relating to Mathematical Compasses or Dividers.
Year: 1894

page_text: Date of Application, 6th Feb., 1894
Complete Specification Left, 6th Nov., 1894-Accepted, 8th Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in or relating to Mathematical Compasses or
Dividers.
I EDWARD WASHBOURN SARGEANT of Brookside, Crawley Green Road,
Luton in the County of Bedfordshire, Engineer, do hereby declare the nature of
this invention to be as follows:-
The object of this invention is to obtain much greater rigidity in a pair of
compasses or dividers, when used for making large circles than can be obtained
with these instruments made as at present and furnished with the ordinary
lengthening bar.
According to this invention I make the lengthening bar round, elliptical or of
other suitable section, and so as to fit into one of the legs of the compasses or
dividers; and this bar may be held in position by means of a socket, and tightening
screw, or by simply pushing it into a socket.
On to this lengthening bar I slide a T socket piece, into which can be put the
ordinary ink, pencil or needle points, supplied with compasses as generally made
so that there are no extra pieces but the sliding T piece.
Or I make the T piece with two arms one for an ink or pencil point and one
for a needle point, such points to be in addition to those usually supplied with
compasses.
The sliding T piece in either case is secured in position on the bar by any
suitable means.
To the knee joint of one leg of the compasses or dividers I fit a screw with
milled head so as to hold it firmly in any required position.
Over the hinge or head joint of the compasses or dividers I fix or form on each
side a projecting piece or shoulder, so that when the two legs are in one straight
line they shall not bend downwards when in use through pressure upon them but
always remain rigid.
Dated this 6th day of February 1894.
BROWNE & Co.,
9, Warwick Court, Gray's Inn, W.C., Agents for Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to Mathematical Compasses or
Dividers.
1 EDWARD WASHBOURN SARGEANT of Brookside, Crawley Green Road,
Luton in the County of Bedfordshire, Engineer, do hereby declare the nature of
this invention and in what manner the saine is to be performed, to be particularly
described and ascertained in and by the following statement :-
The object of this invention is to obtain much greater rigidity in a pair of
mathematical compasses or dividers, when used for making large circles, than can
be obtained with these instruments made as at present, and furnished with the
ordinary lengthening bar.
According to this invention I make the lengthening bar round, elliptical or of
other suitable section, and so as to fit into one of the legs of the compasses or

page_text: dividers; and this bar may be held in position by means of a socket and tightening
screw, or by simply pushing it into a socket.
Onto this lengthening bar I slide a T-socket piece into which can be put the
ordinary ink, pencil or needle point, supplied with compasses as generally made, so
that there are no extra pieces but the sliding T-piece.
Or I make the T-piece with two arms one for an ink or pencil point, and one
for a needle point, such points to be in addition to those usually supplied with
compasses.
The sliding T-piece in either case is secured in position on the bar by any
suitable means.
To the knee-joint of one leg of the compasses or dividers I fit a screw with
milled head so as to hold it firmly in any required position.
Over the hinge or head joint of the compasses or dividers, I fix or form on
each side a projecting piece or shoulder, so that when the two legs are in one
straight line they shall not bend downwards when in use through pressure upon
them, but always remain rigid.
And in order that my said invention may be more clearly understood I will now
proceed to describe the same with reference to the accompanying drawings in
which
Figure 1. shews elevation of a pair of compasses or dividers, with my
improvements adapted thereto;
Fig. 2 shews similar view to Fig. 1; but constructed so as to carry a pen and
pencil, pen and needle point, or pencil and needle point (any two at once);
Fig. 3 shews detail hereinafter referred to.
The same letters denote the same parts in all the views.
a, a shew the ordinary legs of a. compass or divider, 6 my improved lengthening
bar, which in Fig. 1 is oval in cross section, and in Fig. 2 round. The bar bis
held in position in the usual way by means of a socket c. d, d shew two pro-
jections or shoulders formed over the hinge e, so that the legs a cannot be opened
to a greater angle than 180 degrees. n sbews a double T-piece the arms ff of
which are hollow or tubular, so as to slide onto the lengthening bar b as shewn in
Fig. 2, the arms f₁f being provided with ordinary sockets into which the pen,
pencil or point fit." When the bar is made circular in section, the double
T-piece can be turned round in a plane vertical to the bar b, so as to bring one of
the two instruments (pen, pencil or point) into position as required. The piece n
is held in the required position by means of the screw o. g denotes the pen and
h the pencil or point.
In Fig. 1 is shewn a modification of the T-piece_n in this case a projection or
extension socket i is formed over the top of the T-piece for the pen g or pencil
holder to take into, so that the ordinary compass pen can be fitted into said holder.
By this arrangement the length from the bar b to the extremity of the pen, pencil
or point is not greater than the length of the hinged leg k. An end view of this
modification is shewn at Fig. 3. The lengthening barb passes through the
elliptical hole and the said socket i is clamped onto the bar by the screw m.
p is a tightening screw at the joint of the hinged leg k to render the same perfectly
rigid, when it is at right angles to a.
Compasses or dividers constructed according to this invention will be found
more rigid than ordinary compasses or dividers, supplied with the ordinary
lengthening bar, and will be much easier to work with when describing large
circles.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In mathematical compasses or dividers, the pen, pencil or point holder, or
double T-piece n provided with tubular arms ft, substantially as and for the

page_text: 2. The modification shewn at Fig. 3 substantially as and for the purpose set
forth.
3. In compasses or dividers the projections or shoulders d d substantially as
and for the purpose set forth.
4. In mathematical compasses or dividers the tightening screw p at the joint of
the hinged leg k substantially as and for the purpose set forth.
5. The improvements in or relating to mathematical compasses or dividers,
substantially as set forth.
Dated this Sixth day of November 1894
BROWNE & Co.,
9, Warwick Court, Gray's Inn, London, W.C.,
Agents for the Applicant.