IMPROVEMENTS IN THE CONSTRUCTION OF MATHEMATICAL, DIVIDING AND MEASURING INSERTIMENTS
Year: 1883

page_text: LETTERS PATENT to Ansel Leo of 448 Edgware Road and Phoebe Sarah
Marks of 55 Cambridge Street Hyde Park, both in the County of Middlesex
for an Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF MATHEMATICAL,
DIVIDING AND MEASURING INSERTIMENTS"
PROVISIONAL SPECIFICATION left by the said Ansel Leo and Phoebe Sarah
Marks at the Office of the Commissioners of Patents on the 23rd February
1883.
ANSEL LEO, of 448 Edgware Road, and PHŒEBE SARAH MARKS, of 55 Cambridge
Street, Hyde Park, both in the County of Middlesex "IMPROVEMENTS IN THE
CONSTRUCTION OF MATHEMATICAL DIVIDING AND MEASURING INSTRUMENTS."
The object of our said invention is to provide instruments for making multiple
divisions in drawings marking machinery, wheel works, and other analogous
operations, and avoiding the delay which takes place in so doing by the methods at
present in use.
In carrying out our said invention we construct such instruments upon the
principle of the "lazy tongs" forming a number of connected cells of equal size,
and each capable of receiving corresponding angular motion.
We construct such instruments of steel or other suitable material, the bus thereof
being drilled or bored with equidistant centres, in which suitable pins, pivots, or
screws are fitted and upon which pivots the several bara work without looseness or
shaking.
Any desired number of the pivots may be fitted with central points, moveable
or otherwise; or may have small tubes wherein pencils, steel points or needles mity
be inserted for the purpose of marking or scoring. Also antifriction wheels or
rollers may be mounted upon some of the pivots to sustain the weight of the
instrument and keep it parallel with the surface of the paper or other material
operated upon.
In some cases we fit one or more set or sets of additional smaller links or arms
for indicating smaller divisions which bear a certain adjustable proportion to the
larger divisions of the instrument
Longitudinal bars are sometimes also fitted, with or without adjustable screws
and nuts, for strengthening or stiffening and adjusting the instrument
By suitably arranging the construction and centreing of the bars our said
instruments can be adapted to curved and circular work, and the measurement and
division of segments and circles.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Ansel Leo and Phoebe Sarah Marks in the Great Seal Patent Office on
the 23rd August 1883.
ANSEL LEO of 448 Edgware Road and PHŒBE SARAH MARKS of 55 Cambridge
Street Hyde Park, both in the County of Middlesex IMPROVEMENTS IN THE
CONSTRUCTION OF MATHEMATICAL, DIVIDING AND MEASURING INSTRUMENTS
The object of our said invention is to provide instruments for making multiple
divisions in drawings, marking machinery, wheel works and other analogous
operations and avoiding the delay which takes place in so doing by the methods at
present in use
In carrying out our said invention we construct such instruments upon the
principle of the "lazy tongs" forming a number of connected geometrical cells or
parallelograms of equal size and each capable of receiving corresponding angular
motion.
We construct such instruments of steel or other suitable material, the bars thereof
being drilled or bored with equidistant centres in which suitable pins, pivots or
screws are fitted and upon which pivots the several bars work without looseness or
shaking.
Any desired number of the pivots may be fitted with central points, moveable
or otherwise; or may have small tubes wherein pencils, steel points or needles may
be inserted, for the purpose of marking or scoring-Also antifriction wheels or
rollers may be mounted upon some of the pivots to sustain the weight of the
instrument and keep it parallel, with the surface of the paper or other material
operated upon.
In some cases we fit one or more set or sets of additional smaller links or arms
for indicating smaller divisions which bear a certain adjustable proportion to the
larger divisions of the instrument.-Longitudinal bars are sometimes also fitted
with or without adjustable screws and nuts for strengthening or stiffening and
adjusting the instrument.
By suitably arranging the construction and centreing of the bars our said
instruments can be adapted to curved and circular work, and the measurement and
division of segments and circles
And in order that our said invention may be clearly understood reference is hereby
made to the accompanying drawings in which similar letters indicate corresponding
parts in the several figures.
Fig: 1 represents one form of instrument closed and Fig: 2 represents the same
open. The bars a a are jointed to each other by means of pins rivets or screws
at b b. as shewn: the joints being carefully placed so that parallelograms are thereby
formed and the several cells are exactly alike with respect to dimensions and
angles Any or all of the centres b¹. are fitted with points or pencils in order to
measure and indicate equal distances by pricking or marking
The instrument shewn in Figs 1 and 2 is represented as having seven primary
cells or parallelograms but any other desired number may be adopted
Upon the end cell an additional moveable bar c (See also Figs: 3 and 4) is placed―
This bar is perforated with equidistant holes, and the bars a¹ are also perforated to
tally therewith
Fig: 3 is a plan view and Fig 4 is a side view of this bar c which has a point or
pencil at cd, Fig 2, is a retaining bar, of which Fig 5 is a side view, having a
handle d' and two pins d² fitted as shewn-By means of the bar & the bar c can be
placed upon any pair of holes in the two end bars a¹ and the divisions or measure-
ments increased to a very large extent-As shown in the drawing the distance

page_text: from c to b¹ is one thirteenth of the whole distance and the almost unlimited
number of subdivisions of which the instrument is capable will be obvious
The additional bar fis pivotted at 62. and slides through a stud or bolt head at 6.
where a set or binding screw is placed in order that the instrument may be set and
retained as required
By arranging a single cell upon one leg of a pair of compasses as shewn at e
in Figs 6 and 7 the use of the cell or parallelogram is applied in a different
manner
It will be seen on reference to Figs. 6 and 7 that the bars a¹, a³, a³ and the
compass legg together form the parallelogram surrounding the cell e-Also that
the bars a a³ a' and the compass leg g together form a parallelogram, and the
bar a¹ is not absolutely necessary and may if preferred be dispensed with entirely-
The leg g passes through two slides h which are pivotted to the bars a' and a³
the distances from bb being fixed-The leg i passes through similar slides h¹ h¹
but these slides are pivotted to other slides h³ h³ which slide upon the bars a³ a³ as
shewn-A third leg m is fitted, the upper end thereof passing through the sliding
block n, the lower end passing through a single slide h¹ fitted to h' as shown. Set
screws k k are fitted to the two slides on a³ for fixing the respective angles-One
of the bars a' or a³ is divided into any convenient number of parts for the purpose
of dividing
This instrument is a convenient form of proportional compasses-Upon setting
the leg m in any given relative position to the legs g and i and setting the
screws k k―The parallelogram may be slidden up or down the three legs in order
to measure distances in the same proportion, the relative distances being preserved
by this arrangement.
Figs 8 and 9 represent another modification of our invention-This form of
instrument is useful in dividing arcs and segments of circles and also in finding the
centres of arcs and circles with rapidity and precision
Having thus particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed-we claim :-
1. The combination and arrangement of parts together forming the mathematical
dividing and measuring instrument substantially as herein before described
with reference to Figs 1. 2. 3. 4 and 5 of the drawings
2. The arrangement of the cell e in combination with the several parts together
forming the mathematical dividing and measuring instrument substantially as
herein before described with reference to Figs: 6 and 7 of the drawings.
3 The combination and arrangement of parts together forming the mathematical
dividing measuring and centreing instrument substantially as hereinbefore
described with reference to Figs 7 and 8 of the drawings.
4. The manufacture and use of the several mathematical instruments hereinbefore
described and shewn on the drawings or any mere modification thereof.
In witness whereof I the said Ansel Leo on behalf of myself and the said
Phoebe Sarah Marks have hereunto set my hand and seal this twenty second day
of August in the year of our Lord 1883.
Ar THA
(077)
AT CITY