provements in Sliding Indices for Slide Rules.
Year: 1890

page_text: Date of Application, 23rd July, 1890
Complete Specification Left, 22nd Apr., 1891-Accepted, 23rd May, 1891
PROVISIONAL SPECIFICATION
Improvements in Sliding Indices for Slide Rules.
I GEORGE HAUGHTON MEIRE, of Eyton-on-Severn, near Shrewsbury, in the
County of Shropshire, Farmer, do hereby declare the nature of this invention to
be as follows:-
The object of my invention is to manufacture improved sliding indices, or
markers, employed for the purpose of facilitating the use of slide rules, and com-
puting scales. And it consists in making the index of two pieces of suitable metal,
or other suitable material, of particular shape, and preferably, but not necessarily,
of the same shape, and dimensions, and in holding them together, and upon the rule,
and causing them to grasp the rule, by the action of a strained india rubber band,
or by a band of other elastic material, or by one, or more, metallic, or other, springs,
capable of producing the same effects upon the two pieces of metal, or other
inaterial as a surrounding clastic band under tension.
The chief features of novelty in my invention are:--(1) that after the index is
manufactured, and after it is adjusted to fit a rule, it can be put on, or removed
from, the rule by taking to pieces, without injury to the index, or alteration of its
adjustment, and without injury to the rule: (2) that by the provision of certain
small parts for the purpose, the index can be readily adjusted to fit rules which
differ slightly in breadth, or thickness, by bending those parts, also other parts; and
the elasticity of the rubber, or other spring, allow the index in a measure, to adjust
itself to fit rules which differ to an extent in thickness, and to accommodate itself
to the variable thickness of a rule: (3) that the rubber, or other spring, which
causes the index to grasp the rule, also holds together the pieces of which the
index consists (4) that by the provision of certain projections, and corresponding
recesses, any one part of the index is prevented from sliding upon the rule without
the other parts following, when the rubber, or other spring is applied.
The following description relates to the application of my invention to a kind
of slide rule in which the same slide extends through the rule to both faces, and
which is usually graduated with scales on two faces, and made with obstructions at
the ends which render it impractical to put on, and take off the index by passage
over one of the ends of the rule, after both the rule and the index have been con-
structed. From which description the adaptation of my invention to other rules,
and instruments bearing scales upon one face, or upon several faces, or upon a
cylindrical face, may be inferred.
In order that my said invention may be described and ascertained reference is
hereby made to the accompanying drawings in which similar letters of reference
indicate corresponding parts. In Fig. 1. z represents a portion of a slide rule,
y a portion of its slide, a represents one of the metal pieces of the index, and c
the elastic band which surrounds both a and the piece b of the index which is not
shown in Fig. 1.
and
Fig. 2. represents the outline of a, or b, as they may be stamped, or otherwise
cut, from a sheet.
The bevelling of the projections not lettered, and the opposite
edge, as shown in Fig. 1. may be subsequently performed, and the sides marked de
and fg require to be bent at right angles to the part connecting them, as shown
in Fig. 3. which is a section of the rule and its slide, and of the two pieces a and b
of the index at the part indicated by the dotted line p q in Fig. 1. Also Fig. 2. shows
a projection marked m opposite to a recess n of the same dimensions. Fig. 4. shows
the manner in which this projection upon a fits into the corresponding recess on b
and in the same manner the projection on also fits into the recess upon a after

page_text: the sides d e and fg have been bent as described, and a and b are placed in position
on the rule.
The cuts, or openings, shown in Fig. 2. between, or near, daud 4, e and j, f and k,
and between, or near and 1, are made where the angles formed by bending the
sides occur.
And these openings are preferably made after the angles are formed.
The two small parts, or corners, on either side of each of the four openings of a,
and the eight similar corners of bare available for the purpose of adjusting the
index to suit the rule.
Fig. 5. represents a section, on the liners in Fig. 1, of the rule, its slide, four
of the eight corners of a. and four of the eight corners of b; and these corners
of a and bare shown in contact with the rule, as they should be after adjustment
is effected. While by Fig. 3 it is shown that at the part of the index indicated
by the line pg. in Fig. 1. the pieces a and b are not in contact with the rule. The
necessary bend of the corners is indicated in Figs. 1 and 4. Assuming that the
rule and the pieces a and b of the index are of the relative dimensions shown in
the drawings, then by more, or less, bending towards the rule the four corners of a,
and the four corners of which slide upon the edges of the rule, the index can be
adjusted to fit the breadth of the rule; and by more, or less bending towards the
rule the eight corners of a and b which slide upon the two faces of the rule, the
index can be adjusted to fit the thickness of the rule, and at the same time the index
is carried clear of the two faces of the rule and its slide, except at the outside
margins of the rule which it is rarely desirable to graduate with scales.
The openings between the corners bent to fit the breadth, and those bent to fit the
thickness of the rule, may be enlarged, if necessary, and the four corners of a,
and the four of b, which slide upon the two faces of the rule may be further bent,
if necessary, so as to separate the piece a of the index from the piece b, except
where the sides of the projections on a and b are in contact with the sides of their
respective recesses as partly shown in Fig. 4; then the tension of the surrounding
elastic band causes a and b to grasp the rule; and assuming that a and b are made
sufficiently strong, the pressure of their grasp is confined to a direction which does
not increase the requisite pressure of the rule upon its slide.
Dated this Twenty-second day of July 1990
G. H. MEIRE.
COMPLETE SPECIFICATION.
Improvements in Sliding Indices for Slide Rules.
I, GEORGE HAUGHTON MEIRE, of Eyton-on-Severn, near Shrewsbury in the
County of Shropshire, Farmer, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
The object of my invention is to manufacture improved sliding indices or
markers employed for the purpose of facilitating the use of slide rules and com-
puting scales.
My invention consists in making the index of two or sometimes more detachable
pieces of brass or other suitable metal or material (hereinafter generically referred
to as the metal pieces,) of particular shape and preferably but not necessarily of
the same shape and dimensions, and in holding them together and upon the rule
and causing them to grasp the rule by the action of a strained indiarubber band or
by a band of other elastic material under tension, or by one or more metallic or
other springs used to produce the desired effect (hereinafter generically referred to
as the rubber spring).
It is possible although not usual to construct slide rules of various transverse
sections. For instance the transverse section of a cylindrical rule is in outline a circle,
that of a rule with three flat faces is a triangle, the section of the rules generally
made is a rectangle, but the section may be a regular or irregular figure of any

page_text: number of sides. To manufacture the index under consideration to suit rules of
triangular section, or of a section consisting of an odd number of sides, it would
probably be desirable to use more than two metal pieces to be grasped by the
rubber spring. Such indices are not likely to be required because rules of the kind
are not likely to be made, particularly when the slide extends through the rule and
is visible upon more than one face of the rule. And it is for use upon rules of this
kind that my index is chiefly intended. At the same time it is serviceable upon
those rules which are made so that the slide is visible upon only one flat face, and it
can be manufactured for use upon a rule of any section.
The following description relates to the application of my invention to a slide
rule of rectangular section, with its slide extending through the rule and visible
upon two opposite faces of the rule (the two faces generally graduated). From
which description the adaptation of my invention to other rules and instruments
bearing scales upon one face, or on several faces, or upon a cylindrical face may be
inferred.
In order that my said invention may be particularly described and ascertained
reference is hereby made to the drawings left with the Provisional Specification, in
which similar letters of reference indicate corresponding parts. In Fig. 1. repre-
sents a portion of a slide rule, and y a portion of its slide. a represents one of the
metal pieces of the index, and c the rubber spring which surrounds a and the other
metal piece not seen in Fig. 1. but shown in Fig. 4.
The tension of c causes a
and to grasp the rule.
Fig. 2 represents the outline of a or bas they may be stamped or otherwise cut
from a sheet. The bevelling of the projections not lettered, and the opposite edge
as indicated in Fig. 1. may be subsequently performed, and the sides marked de
and fg, require to be bent at right angles to the part connecting them. as shown in
Fig. 3. which is a section of the rule and its slide, and of the two metal pieces a
and b of the index at the part shown by the dotted line p q in Fig. 1. Generally
it will be found advisable to bend the sides at right angles before any of the inter-
vening indentations have been cut away.
Fig. 2. shows a projection marked m. opposite to a recess n of the same dimensions,
and Fig. 4 shows the manner in which this projection upon a fits into the corre-
sponding recess on b. In the same manner the projection on balso fits into the recess
upon a, after the sides de and.fg have been bent as described, and a and b are
placed in position on the rule. And thus a cannot be longitudinally traversed upon
the rule without b following when the projection m. on each is placed in the recess n
on each. The same result would also follow if either a or b carried the two
projections and the other piece the two recesses.
The cuts or openings shown in Fig. 2. between, or near, d. and h, e and j, f and k,
and between or near y and l. are made where the angles formed by bending the sides
occur. And these openings are preferably made after the angles are formed. The
two small parts, or corners, on either side of each of the four openings of 12, and
the eight similar corners of 6 are available for the purpose of adjusting the index to
suit the rule.
Fig. 5. represents a section on the liners in Fig. 1. of the rule, its slide, four of
the eight corners of a and four of the eight corners of b, and these corners of a
and are shown in contact with the rule as they should be after adjustment is
effected. (Note:-Generally it is advantageous to allow a very small space between
the edges of the rule and the corners of the index which slide upon them.) While
by Fig. 3. it is shown that at the part of the index indicated by the line p q in
Fig. 1. the pieces a and b are not in contact with the rule. This follows because
the corners are bent, and the necessary bend is indicated in Figs. 1 and 4.
Assuming that the rule and the metal pieces a and b of the index, are of the
relative dimensions shown in the drawings then by more or less bending towards
the rule the four corners of a and the four of which slide upon the edges of the
rule, the index can be adjusted to fit the breadth of the rule, and by more or less
bending towards the rule the eight corners of a and b which slide upon the two faces

page_text: of the rule, the index can be adjusted to fit the thickness of the rule, and at the
same time thb index is carried clear of the two faces of the rule, except
at the outside margins of the rule which it is rarely desirable to graduate with
scales.
The openings between the corners bent to fit the breadth, and those bent to fit
the thickness of the rule may be enlarged if necessary, and the four corners of a and
the four of which slide upon the two faces of the rule may be further bent if
necessary, so as to separate the piece a from the piece b. except where the sides of
the projections on a and b are in contact with the sides of their respective recesses,
as partly shown in Fig. 4. then the tension of the surrounding rubber spring causes
a and b to grasp the rule. And in a measure the index is free to adjust itself to fit
rules which differ to an extent in thickness, and to accommodate itself to the variable
thickness of a rule.
Assuming that a and b are made sufficiently strong, they cannot be pressed by the
rubber spring upon the edges of the rule, and thus the requisite pressure of the rule
upon its slide is not interfered with by the index.
After the index is manufactured and adjusted to suit a rule it still consists of
detachable parts. And even when the rule is made with obstructions at the ends,
the index can be put on, or taken off the rule, without injury to either rule or index,
or alteration of the adjustment of the index.
As regards the adjustment of a and b by bending their corners.
This is a
convenient way of effecting adjustment when a and b are made of a material
suitable for bending. But if made of a brittle material which may have been
cast or moulded, adjustment could be effected by reduction, if a sufficiency of
material were provided at the parts for adjustment by removal with a file or
otherwise.
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:-
The combination in the construction of a sliding index for slide rules of two or
more metal pieces surrounded by a rubber spring. (The terms "metal pieces" and
"rubber spring" are both used generically as previously explained.) The metal
pieces being of such strength and so formed that pressure exerted by the rubber
spring upon the pieces above mentioned and conveyed by them to the rule can only
act in directions which cannot cause, or increase, pressure of the rule upon its slide
when the transverse section of the rule is rectangular; and when the rule is of other
section any pressure derived from the index which reaches the slide of the rule is
slight, if any. The metal pieces being also so formed that when in position on a
rule to which they are adapted the inter-locking of the projections and corresponding
recesses provided for the purpose prevents one of those metal pieces being
longitudinally traversed upon the rule without the other metal piece or
pieces following, substantially as hereinbefore described and illustrated by the
drawings.