Year: 1888

page_text: Date of Application, 12th June, 1888
Complete Specification Left, 12th Mar, 1889
Complete Specification Accepted, 27th Apr, 1889
I, CALVIN MILLFR DUNHAM, of 1024 Edmond Street, in the City of St Joseph,
County of Buchanan, State of Missouri, United States of America, Clerk of United
States Circuit and District Courts, do hereby declare the nature of this invention to
bu is follows
-
This Invention consists in an adjustable interest indicator or calculator, whereby
not only manual libor is largely reduced but mental labor almost entirely dispensed
with in ascertaining the amount of interest on different sums of money at,different
rates of interest for different periods of time, the whole forming what may be termed
an instantaneous interest indicator or calculator
The device is a double one, that is to say, it is supposed to be similarly constructed
and operated on both or opposite sides, one side being for one kind of money as
for instance one side for American money and the other side for English money,
but it will suffice here mainly to describe it as of single construction by referring
more particularly only to its one side as arranged for dollars and cents but which, so
far as the invention is concerned, might be arranged for pounds, shillings, and pence,
or other kinds of money
The frame is in the form of a box, the sides of which may be hinged at top to open
and close, either side having a longitudinal aperture in it which aperture is preferably
made larger at one end Longitudinal rollers are mounted within the box, one above
the other, in proximity to its apertured side These rollers, which may be turned by
knobs outside the end or ends of the box, carry and operate a tabular sheet which
constitutes a movable principal and interest web This web is arranged to present a
facial exposure between the rollers immediately in rear, or inside, of the aperture
and may be worked up or down, by turning the upper or lower roller according to
the principal and rate of interest on the web it is required to expose Arranged
lengthwise over the narrow portion of the aperture, is a fixed time indicator divided
up into a horizontal row of spaces marked to indicate different periods of time ranging
Say from one year to one day, but which are arbitrary and may be extended or
diminished as required

page_text: The principal and interest web 15 divided up on its face into vertical columns
running lengthwise of the web, which columns are divided by cross-lines into
horizontal rows of spaces, there being say three such horizontal lines of spaces
opposite each space of the first or marginal column The spaces of the first or
marginal column contain the different amounts of principal, each space containing
one such sum The next succeeding column contains the different rates of interest
per annum, say six, eight, and ten per cent respectively, these three figures
appearing in the three squares opposite each square of the principal column
The rows of spaces of the succeeding columns (which correspond in alignment with
the time indicator) contain the amounts of interest at these various rates of interest,
of the sums of principal marked in the spaces of the principal column opposite which
they are placed for the different periods of time marked on the indicator spaces,
with which the columns are in alignment Only one transverse row of spaces 18
exposed through the aperture, the principal sum and different rates of interest being
seen through the enlarged end portion of said aperture The narrow part of the
aperture is closed by a series of what may be termed flexible covers corresponding
to the spaces of the time indicator These flexible covers may be simple pieces or
tablets of tin, brass, or other met il or material hinged upon wire run along the top
of the slot or aperture, or they may be otherwise suitably constructed and bung to
open and close
To ascertain the amount of interest, at either of the rates indicated, it is only
necessary to turn the rollers until the amount of principal, upon which it is required
to ascertain the amount of interest for a given time, is exposed through the end
portion of the aperture and the given rate of interest is in line with the narrow
part of the aperture, and then to lift the flexible cover or covers under the periods of
time in the space or spaces of the fixed time indicator which shew the period or periods
the interest is to be calculated for, and the amount of interest for such time or times
will be exposed on the uncovered squares or spices Thus supposing it be required
to ascertain the amount of interest on $1000 at the rate of 80% per annum for five
months or for twelve days, upon lifting the flexible covers under those periods of time
on the fixed time indicator, the amounts of interest for those periods of time for the
exposed principal will be given or exposed on the web as $33, and $2,70
respectively

page_text: I CALVIN MILLER DUNHAM of 1024 Edmond Street, City of St Joseph, in the
County of Buchanan and State of Missouri, United States of America, Clerk of
United States Circuit and District Courts do hereby declare the nature of this inven-
tion ind in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement
-
This invention consists in an adjustable interest. indicating table or calculating
device, whereby not only manual labor is largely reduced but mental labor almost
entirely dispensed with in ascertaining the amount of interest on different sums of
money, at different rates of interest, for different periods of time, the whole forming
what may be termed an instantaneous interest indicator or calculator
Reference is to be hid to the accompanying drawings forming a part of this
specification in which figure 1 represents a view in perspective of an interest
indicating device embodying my invention Figure 2 is a transverse section of the
same, and figure 3 a face view of a portion of a movable principle and interest
table used in the device The same letters of reference indicate the same parts in
all the figures
The device as represented is double one, that is to say it is supposed to be
similarly constructed and operated on both or opposite sides, one side being for one
kind of money, as for instance, one side for American money and the other side for
English money, but it will suffice here mainly to describe it as of single construction,
by referring more particularly only to its one side, as arranged for dollars and cents,
but which, so far as the invention is concerned, might be arranged for pounds, shillings
and pence, or other kinds of money
A is the frame in the form of a box, which may be made of metal, wood, or other
suitable material, and the sides of which may be hinged at top to open and close,
either side having a longitudinal aperture 6 61 in it, which aperture is preferably made
larger at its one end portion as at 61 The shape of the box may be varied as
desired
B B are longitudinal rollers within the box arranged one above the other in
proximity to its apertured side These rollers, which may be of wood, metal, card-
board or other suitable material and may be turned by attached knobs c outside
the end or ends of the box, have attached to them and serve to carry and operate a
tabular sheet which constitutes a movable principal and interest web C This web
may be made of paper, linen, cloth, or other suitable and flexible material and is
arranged to present a facial exposure between the rollers immediately behind or inside
of the aperture 6 6' and may be worked up or down by suitably turning the upper
or lower roller according to the principal and rate of interest on the web it is required
to expose
Arranged lengthwise over the portion 6 of the aperture is a fixed time indicator D-
divided up into transverse spaces à marked to indicate different periods of time, here
shown as ranging from one year to one day, but which are arbitrary and may be
extended or diminished as required
The principal and interest web C is divided along and across its face into columns
and rows of spaces
The spaces of the first column near the one margin of the
web are respectively marked with different amounts of principal ranging say, when

page_text: the principal is American money, from $1 to $5000, more or less, whilst the remaining
columns are subdivided into squares or spaces zk, there being say three rows of such
spaces running widthwi
wise of the web opposite each of the spaces of the principal columnƒ
The three squares of the first column g opposite each space e of the principal column
are marked with the three different rates at which interest is required to be calculated,
here shown as 6, 8 and 10 per cent, but these rates may be varied in amount and number.
The corresponding rows of squares k of the succeeding columns h are marked with the
different amounts of interest, at these rates of interest per annum, for the different
periods of time marked on the spaces d of the indicator D, with which the columns hare
arranged to register Only one row of spaces k in the direction of the width of the
web will be exposed through the portion 6 of the aperture, while the principal sum
in any one space e of column and the different rates of interest in the corresponding
spaces of column 9 will be visible through the enlarged portion of said aperture
The portion 6 of the aperture is provided with a series of what nav be termed flexible
covers E corresponding in number and position to the spaces d of the time indicator D
These flexible covers may be simple pieces or tablets of tin, brass or other metal or
material hinged upon a wire 7 run along the top of the slot or aperture b, or they may
be otherwise suitably constructed and hung to open and close
To ascertain the amount of interest, at any one of the rates per annum indicated
in the spaces on any principal sum marked in column 9, it is only necessary to turn,
the rollers B B until the amount of principal upon which it is required to ascertain
the amount of interest for a given time, is exposed through the portion 6' of the
aperture and the given rate of interest is in line with the part 6 of the aperture, and
then to lift, with the point of a pencil or otherwise, the flexible cover or covers E
under the periods of time in the space or spaces d of the fixed time indicator D
which show the period or periods the interest is to be calculated for, and the amount
of interest for such time or times will be exposed on the uncovered squares or spaces k
Thus, as shown in figure 1, supposing the principal exposed to be $1000 and it be
required to ascertain the mount of interest at the rate of 8 per cent per annum for
five months or for twelve days, then upon lifting the flexible covers E under those
periods of time on the fixed time indicator D, the amounts of interest for those
periods of time for the exposed principal will be given or exposed on the web
as $33, and $275 respectively
8.
100
Having now particularly described and ascertained the nature of the sad
invention and in what manner the same is to be performed, I declare that what
I claim 18-
1 The within described interest indicator or calculator constructed for operation,
substantially as specified
2 An interest indicator or calculator consisting of a frame containing rollers,"
movable principal and interest web operated by the rollers, a fixed time indicator,
and a series of flexible covers, all constructed and operated as herein shown and
described
In an interest indicator or calculator, the combination, with the frame A,
indicator D, and interest web C, of the flexible covers E
Dated this 12th day of March 1889