IMPROVEMENTS IN INSTRUMENTS TO BE EMPLOYED IN SETTING OUT OR DRAWING GEOMETRICAL FIGURES AND MORE PARTICULARLY IN GRADUATING CIRCLES
Year: 1884

page_text: I FRANCES HARIOTT WOOD of Acton Green Chiswick in the County of
Middlesex, Spinster do hereby declare the nature of my Invention for
IMPROVEMENTS IN INSTRUMENTS TO BE EMPLOYED IN SETTING OUT OR DRAWING
GEOMETRICAL FIGURES AND MORE PARTICULARLY IN GRADUATING CIRCLES to be as
follows:-
My invention has reference to instruments of the kind described in the
Specification of former Letters Patent granted to me and dated 26th April 1883
N° 2114.
With the instruments therein described the number of regular figures into which
a circle can be graduated is limited by the number of the radial lines in which the
holes for the pencil are formed.
Now one object of my present invention is to allow of a circle being graduated
by means of the instrument into any regular figure. For this purpose I make the
two sides of the sector of bars of wood or other material divided off into inches or
parts of inches and I make one of these sides movable on its centre so that it can
be caused to approach the other side and form any desired anglo therewith
according to the particular graduation required. And for the purpose of securing
it at the desired angle I form a groove or slot therein and another groove or slot in
a bar which forms the connecting line of the two sides of the sector, and when
adjusted I fix it to this bar by a screw or otherwise. This bar is marked off iu
degrees so that the angle required can be at once seen.
For the purpose of allowing a circle to be struck of any desired diameter I fit a
slide on either of the bars of the sector so that it can be adjusted to the required
radius. To this slide I fix a vertical tube or sheath for the pencil employed in
drawing the circle; by passing the pencil into the tube its point will rest upon the
paper or other surface.
Daindhi 10th day of T, 1001

page_text: I FRANCES HARIOTT WOOD of Acton Green, Chiswick in the County of
Middlesex, Spinster do hereby declaro the nature of my invention for "IMPROVE-
MENTS IN INSTRUMENTS ΤΟ BE EMPLOYED IN SETTING OUT OR DRAWING
GEOMETRICAL FIGURES AND MORE PARTICULARLY IN GRADUATING CIRCLES and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:
My Invention has reference to instruments of the kind, described in the
Specification of former Letters Patent granted to me and dated 26th April 1883
N° 2114.
With the instruments therein described the number of regular figures into which
a circle can be graduated is limited by the number of the radial lines in which the
holes for the pencil are formed.
Now one object of my present invention is to allow of a circle being graduated
by means of the instrument Into any regular figure. For this purpose I make the
two sides of the sector of bars of wood or other material divided off into inches or
parts of inches and I make one of these sides inovable on its centre so that it can
be caused to approach the other side and form any desired angle therewith according
to the particular graduation required. And for the purpose of securing it at the
desired angle I form a groove or slot therein and another groove or slot in a bar
which forms the connecting line of the two sides of the sector and when adjusted
I fix it to this bar by a screw or otherwise. This bar is marked off in degrees so
that the angle required can be at once seen.
For the purpose of allowing a circle to be struck of any desired diameter I fit a
slide on either of the bars of the sector so that it can be adjusted to the required
radius. To this slide I fix a vertical tabe or sheath for the pencil employed in
drawing the circle; by passing the pencil into the tubo its point will rest upon the
paper or other surface.
The annexed drawings represent an instrument made according to my present
invention. Figure 1 shows the complete instrument with the parts in position;
Figure 2 shows separately the three bars of which the instrument is mainly
composed. Figure 3 shows the slide and sheath. Figure 4 a bar to be employed
when the instrument is required to be used as a T square. Figures 5 to 9 are
detail views. A and B aro respectively the two sides of the sector divided off into
inches or parts of inches. They are jointed together at one end so that the one
can be moved relatively to the other so as to form any desired angle therewith.
The form of the joint may vary; that shown is composed of a stud a on the side A
and of a hole b in the side B, the hole b being passed over the stud a. The stud a
is screw threaded externally to receive a nut for fixing the two sides A, B in the
position to which they have been adjusted; it is also hollow to give passage to a
pin (Figure 9) for attaching the instrument to the paper and formning the
"centre" of the instrument. C is the bar which forms the connecting line of the
two sides of the sector. It may either be permanently fixed to the side B or be
attached thereto by means of a screw d'and nut & (Figures 5 and 6) as shown;
and in order to ensure that the angle between B and C shall be a right angle so
that the instrument may be used as a set square there is a hole fin B to receive a
small stud or projection g on C. The bars A and C are each formed with a slot
marked D and E respectively, and are connected together by a sliding piece G
(shown separately in Figures 7 and 8) which has a threaded pin passing through

page_text: the two slots and receiving a nut i. While the angle of the bar A with the bar B
is being adjusted the pin h slides in the slots D, E and when the desired anglo has
been obtained the nut is screwed up to fix the parts in place. The bar C is
marked off in degrees as shown so that the anglo required can be at once seen.
I is the slide; it is fitted over the bar A and when it has been adjusted to the
required radius which can be seen through the opening it is fixed by screwing
the lower end of the tube I into holes mado for the purpose in the slide. The
tube I forms a sheath for the pencil, pen or brush employed in drawing a circle,
for which purpose the pencil, pen or brush has merely to be passed into the tube
so that its point may rest on the paper or other surface while the circle is being
described.
a
When it is required to employ the instrument as a T square tho bars A and C
are disconnected from the bar B, the bar T, Figure 4, is then placed upon the
bar B at right angles thereto as shown in dotted lines in Figure 1 and then fixed
thereto by one of the nuts. To ensure that the two bars shall be at right angles
there are holes l, in the bar T to fit over studs m, m on the bar B.
Having now particularly described and ascertained the nature of any said
Invention, and in what manner the same is to be performed I declare that what
I claim is :-
1. Constructing instruments of the kind berein referred to in such manner that
the angle between the sides of the sector can be varied as desired, one of the said
sides and the bar which connects the sides being slotted or grooved for the purpose
of enabling the sides to be fixed at the desired anglo, substantially as and for the
purpose herein before described, and as represented in tho annexed drawings.
2. Constructing instruments of the kind herein referred to with a slide to fit over
one of the sides of the sector and with a shoath or tube attached to the said slido
substantially as and for the purpose herein beforo described and as represented in
the annexed drawings.
3. The improved instrument hereinbefore described and represented in tho
annexed drawings to be employed in setting out or drawing geometrical figures.
Dated this 9th day of October 1884.
J. C. MEWBURN,
169, Fleet Street, London,
Agent for the Applicant.