Improvements in Dividers or Compasses.
Year: 1890

page_text: Date of Application, 23th Apr., 1890
Complete Specification Left, 28th Jan., 1891-Accepted, 7th Mar., 1891
PROVISIONAL SPECIFICATION.
Improvements in Dividers or Compasses.
I, FRANK SAMUEL PETT, of 113, Snargate Street, Dover, in the County of
Kent, Master Mariner, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in dividers or compasses and it has for
object to permit two measurements to be taken at one time with the same
instrument.
My improved instrument may be composed of two similar pairs of compasses or
dividers; those in which the legs bent to cross each other open by squeezing them
together at the upper part; 1 unite these dividers by a hinge joint (which is at
right angles to the joints of the two pair of dividers) each leg of the hinge joint is
secured to its respective pair of dividers by the screw or pin upon which they the
legs of the dividers pivot in opening and closing, I extend one leg or both legs of
the hinge joint downward to the point where this slot is exactly over where the
legs of the dividers cross in opening and closing, it indicates that the hinge joint is
vertical as it must necessarily be before opening out the other dividers hinged
thereto, or I may dispense with one of the four legs leaving the combination other-
wise the same as above described.
With dividers or compasses thus constructed I may measure the latitude upon a
chart and at the same time take the measurement for longitude and thus place the
position of the ship on the chart with one move of the instrument.
Dated this Twenty-eighth day of April 1890.
For the Applicant
W. E. GEDGE,
Agent
COMPLETE SPECIFICATION.
Improvements in Dividers or Compasses:
I, FRANK SAMUEL PETT, of 113, Snargate Street, Dover, in the County of
Kent, Master Mariner, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
This invention relates to improvements in dividers or compasses and it has for
object to permit two measurements to be taken at one time with the same
instrument.
My improved instrument may be composed of two similar pairs of compasses or
dividers, preferably those in which the legs bent to cross each other open by
squeezing them 'together at the upper part; or 1 may dispense with one of the four
legs, the combination remaining otherwise the same as if two pair of compasses or
dividers were united, and as I now give preference to the use of three legs only I
have represented this construction of dividers upon the accompanying sheet of
drawing both in its application to dividers having bent legs and those having
straight legs.
Figure 1 being a perspective view of compasses or dividers with bent légs
embodying my improvements.
Figure 2 showing the legs of same laying down the position of a vessel' upon a
chart" and-
Figure 3 a perspective view of dividers with straight legs with my improvements
applied:

page_text: L pin taking into opposite leg when dividers close.
It will be seen that I unite the dividers by a hinge joint I which is at right
angles to the joint of closing.
I extend one leg or both legs of the hinge joint I downward to the point where
the legs cross when closed, providing this extension D with a vertical slot E, which,
when exactly over where the legs of the dividers cross in opening and closing will
indicate that the hinge joint is vertical, as it must necessarily be before opening out
the leg A.
It will be seen that in the dividers with straight legs shown Figure 3 I use the
same combination of joints with the extension D and slot E. The extension D
being kept vertical by means of a stud or its equivalent working in slot E, the stud
also forming the pin that the hinge joint pivots on in opening or closing each end
of the hinge joint being attached by a screw or pin to their respective legs so that
on the dividers being opened or closed the hinge joint causes the extension D to
remain vertical.
With dividers or compasses thus constructed I may measure the latitude upon a
chart and at the same time take the measurement for longitude, thus placing the
position of the ship on the chart with one move of the instrument, as will be seen
by reference to Figure 2 of the drawing; operating as follows:-
Say I want to place the ship's position on the chart and that it is 50° 30' N. Lat.
and 1° 30' E. Long. :
I first place the leg B of the dividers on 50° N. and squeeze the dividers until
the leg C, and with it the leg A, touch 50° 30' N. Lat. (the leg A is carried out as
far as the leg C by means of a stud or pin that fits into the leg C.) or in other
words I measure degree Lat. between the compass points B and C; after this I
shift the dividers and measure degree Long, between compass points C and A. I
then place the leg B on 50° N. Lat. and on the meridian of 1° E. Long., the leg C
also on the meridian of 1° E. and will consequently be 50° 30' N. Lat. and 1° E.
Long, the leg A will then be 50° 30' N. Lat. and 1° 30' E. Long.
may make my improved dividers or compasses of any suitable material and
dimensions and, as aforesaid, instead of a single leg A. I may unite two pairs of
dividers by means of hinge joint I, the construction remaining in other respects
substantially as herein before described and shown on the drawing; the hinge K
forming in this case the pivot for the pair of dividers to pivot on instead of the
single leg A. The stud H on the extension D might travel inside the circular
parts of the dividers instead of in the slots G, but I give preference to the use of
the slots.
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. Dividers or compasses constructed and combined so that when they are opened
out lines connecting the three compass points form a right angle, substantially as
herein before described and illustrated on the drawing.
2. In dividers or compasses whether having three legs as shown, or four legs as
above set forth, the extension D, of the hinged joint I, having the slot, or its
equivalent E, in combination with the slots G, or their equivalent, by the stud H, or

page_text: its equivalent, the whole arranged to work substantially as described for the
specified.
purpose
3. In díviders or compasses having a single leg A attached to a pair of dividers
by means of a hinge joint 1, and the pair of dividers having the extension D, slots E
and G and stud H, or their equivalents, the hinge K substantially as described for
the purpose specified.
4. Dividers with straight legs constructed combined and arranged to operate
substantially as herein before described with reference to Figure 3 of the drawing.
Dated this Twenty-eighth day of January 1891.