IMPROVEMENTS IN CALCULATING AND ADDING MACHINES
Year: 1885

page_text: I, EDWARD HALSEY, of San Jose in the County of Santa Clara and State of
California, one of the United States of America, Accountant, do hereby declare
the nature of my invention for "IMPROVEMENTS IN CALCULATING AND ADDING
MACHINES "to be as follows:-
This invention relates to machinery or apparatus for multiplying dividing and
computing taxes and percentage, and adding columns of figures; and it consists
essentially in the combination of a plate provided with a series of slots or openings
and a number of slides, and in certain arrangements of figures all has hereinafter
described.
The said apparatus when arranged comprises a board or tablet forming the base
of the machine and a top plate which covers the face of the board excepting a
portion at one end where certain indicating lines and figures are located.
The said top plate while being firmly secured in place is set clear of the face of
the board in order to leave a space or way for a number of, slides and this space is
divided by means of the pins into separate passages across the board, into each of
which a slide is held and guided. These slides move easily to and fro in these
guides from the left hand end of the board, and they are turned up at this end to
form stops and finger pieces. At this end also is an index point or line that is used
for setting the slides to the required lines of an indicator on the board in the
operation of making a calculation.
The lines of the said indicator are spaced and numbered from 0 to 8 inclusive
beginning at the end nearer the edge of the plate; these numbers being placed at
the top and bottom.
Each slide is likewise divided by transverse parallel lines into spaces of equal
width and when any number of slides are set to the lines of the indicator, the
spaces on the slides will register and be in direct line over one another.
In the top plate are formed rectangular openings ten in number, each of suitable
width to uncover and expose 8 of the spaces on each slide and of such length that
such portion is exposed on the whole 9 slides: nine of these spaces are designated
by numbers from 1 to 9 inclusive, the tenth and last opening not being numbered
with them as it is employed for calculating interest and is not used in connection
with the indicator, and the other openings except in working such examples.

page_text: ;
Operations in multiplication and division are performed only with the other nine
врасев.
Each slide is designated by a number placed along the edge of the top plate
beginning with number "1" for the lowest slide and ending with number "9" at
the top one.
In the machine described the indicator and the spaces appropriated to each
opening in the top plate one arranged to perform calculations in Figures covering
8 places or up to ten millions the extreme right hand line on the indicator and
the extreme right hand space on each slide in each of the openings being units the
next one tens and so on to the 8 places.
The slides are numbered in these spaces in the following manner the unit spaces
on the first or lowest slide seen at the extreme right throughout the whole number
of nine spaces shew the several products obtained by multiplying the number of
the slide by the number designating the opening and thus in opening "1" is seen
the number "1" in opening 2 the number 2 in opening 3 the number 3 and so
on, one being the product of the slide number multiplied by the opening number.
In the same manner slide number 2 is provided with the numerals 2, 4, 6, 8, 10, 12,
14, 16, 18 exhibited in the openings from the left to right slide 3 with the numerals
3, 6, 9, 12, 15, 18, 21, 24, 27, and in the same manner throughout the remaining
6 slides.
These slide numerals are in a vertical column along the right hand edge of each
opening when the points of all the slides are set to register with line 1 on the
indicator.
The opposite ends of the slides that work in connection with the tenth opening
are covered by the top plate when the slides are thus set, but are divided into spaces
which are marked as follows, on the end of the slide 1 the figures 277777. on slide 2
the figures 555555, on slide 3 the figures 833333, on slide 4 the figures 11, 11, 11
and on slide 5 the figures 1388888. The remaining slides carry the following
figures respectively slide 6, the figures 1666666, slide 7 the figures 1944444, slide 8
the figures 2222222, and slide 9 the figures 2499999.
These figures represent decimally the interest at one per cent per year of 360
'days for one day on the number of dollars represented by the slide number.
The space uncovered by the tenth opening is divided into two parts by a thread
"or wire stretched perpendicularly across it and which marks the division between
dollars and cents in the row of figures on each slide in the various operations
performed where this space is employed. The operation of the machine in multi-
plying figures will be understood by performing the following example, viz by
multiplying 219375 x 849.
:
Now as the multiplicand contains figures to the sixth place or to hundredths of
thousands and the first figure to be multiplied is 2 the slide corresponding to that
number is drawn out to the thousands place, or until its point register with line 6
of the indicator; the first slide is drawn out to the fifth place or line 5; the next
slide is set to the fourth place, the third slide to the third place, the seventh slide
to the second place, and the fifth to the first or units place, on the indicator.
Then from the opening 3, 4 and 9 in succession are taken the sums that will be
obtained by adding up the several columns of figures exposed the numbers of the
openings thus taken being those of the multiplier given, and resulting sums will
be as follows.
From opening 3 the sum 658125, which results from the adding of several

page_text: gives the product required.
The operation of division is simply the reverse of that required in multiplying.
the slides being set in the same manner with reference to the lines of the indicator
to give the figures of the division and then, by examination of the figures seen in
the openings the sum that can be found the nearest to the dividend taking as many.
figures thereof as the division is seen to go into it is ascertained, and the number
of the opening in which this sum is found will be the first figure of the quotient. :
This sum being substracted and a new dividend formed in the usual manner the:
openings are again examined to obtain in one of them the sum nearest to that of
the new dividend, and when found the number of the opening shows the second
figure of the quotient, and so on until the example is finished.
The method of calculating interest by means of the machine is based on the
principle of finding the amount which in one day at one per cent per year will
produce the same amount of interest as a given sum at a given rate for a given
time will produce, and then by setting the slides to the lines of the indicator
according to the sum ascertained, the given interest will be the sum of the figures
exposed to view in the tenth opening.
The figures to the left of the thread are dollars and those on the right are cents
and decimal parts.
The following example in simple interest will illustrate the mode of operation to
find the interest on $625 at 3 per cent for 3 months 27 days.
This will be equal to $1877 at 1 per cent for the same time or 117 days,
or 1877 x 117 will be interest at 1 per cent for 1 day on 219375.
Having set the slides from 6 to 1 inclusive to register with the lines 2, 1, 9, 3, 7, 5,,
respectively on the indicator the following figures will be exposed in the tenth.
opening.
6-090
which is the required sum of $6.09 the interest on $625.00 for the given time.
The apparatus as arranged for adding columns of figures is also provided with a
board or tablet having a top plate fixed to and over its upper face in such manner
that a small space is left between the plate and tablet to admit a slide? By means
of wire pins, driven through the top plate firmly into the board beneath at
intervals apart crosswise and in several sets lengthwise of the board this space is
divided into grooves, the number of which will depend on the number of slides
used. Each slide being held and guided by the pins is easily moved out from
under the top plate and is confined between these guides so as always to hold its
position in line with a slot or long opening in the top plate through which is
exposed a portion of the face of the slide beneath.
;
+
The machine hereinafter described has the capacity of adding any number of
figures together as high as 250 in a single column and for convenience in
manipulating as well as for general compactness in form and size these numbers
are distributed among tive slides each carrying fifty numbers. On the first'slide is '

page_text: marked the numbers from one to fifty inclusive on the second from fifty one to one
hundred inclusive and so on through the remaining slides. ---
These numbers are arranged along the face of the slides and at regular distances
apart along one side of the middle from end to end, each number being immediately
opposite a circular hole so that the slide has in addition to the line of figures a row
of holes or perforations as many in number as there are numbers placed on the
slide. This row of perforations is arranged in line along the left side of the slide
from end to end. Each slide therefore contains fifty of such perforations suitably
numbered in regular order.
To each slide also the top plate forms a cover and screen except for that portion
visible through a slot or opening and the length of this slot is made equal to the
space taken up by nine of the spaced perforations, so that nine of the perforations
are exposed to sight, the remaining surface of the slide including all the numbers
as. well as being covered by the top plate. The slides are turned up to the ends to
furnish stops by which the slides are kept from being moved too far under the top
plate.
These turned up ends also form finger pieces for convenience of moving the
Blides when desired to do so by hand.
At each slot or opening, is marked a scale consisting of the nine digits beginning
with number one at the top and ending with number nine at the bottom, the
intervals between the numbers being made to correspond with those between the
perforations.
Thus each of the nine perforations seen through the slot is identified by a
number on the row of digits along the slide. The operation of these parts as thus
. constructed and combined will be best understood by showing the manner of
performing an example in addition of a single column of figures and as an
illustration the following figures may be taken to find their sum:-viz 4, 6, 5, 3, 8,
6, 5, 8, 9, 7, 2, 5, 4, 3.
The slides are moved by inserting the end of a style or pencil into the
perforations in the slide opposite those numbers of the row of digits of the scale
corresponding to the numbers required to be added one at a time being moved
outwards each time until the pencil strikes the head of the slot.
Into the perforation exposed through the slot directly opposite the number" 4"
and corresponding to the first number in the example, place the point of the
pencil and push out the slide until the pencil is stopped by the head of the slot;
then removing the pencil point place it in the perforation opposite "6" of the
scale and proceed in like manner to take each number of the column from the
scale until the number is reached, when it will be found that the second slide must
be brought into service because the sum produced by adding the 9 to that already
obtained will exceed the capacity of the first slide by 4.
Where a machine is formed of longer slides however a greater number of figures
may be carried on each slide.
In this case the example requires the second slide, upon which the remaining
figures are worked in the same manner one after the other by placing the pencil
point into the perforations in succession, opposite the numbers as taken from the
scale. When the last figure is taken from the scale and the slide moved by the
pencil, the aggregate will be shown by the highest number that is exposed on the
slide at the end of the top plate and in the case of an example requiring two or
more slides to be used, then the last slide will show the required amount.
In constructing these slides I have made them of strips of thin sheet metal, with
the perforations punched through the strips, and of a backing afterwards fixed
upon the bottom or lower face to prevent the point of the pencil or other
instrument from scratching or marking the board beneath.
The apparatus as arranged for computing taxes and percentage also comprises
a board or tablet forming the base of the machine and a top plate covering about

page_text: 'one-nail of the surface and also raised suiciently to auord a space or way a
number of slides.
By means of pins placed in rows across the board this space is divided into
separate grooves to hold and guide the slides which are fitted to move easily in and
out under the plate.
The end of each slide is turned up to form a stop that serves also for a finger
piece to work the slide.
At the inner edge of the top plate is an opening of peculiar shape that uncovers
and exposes to view a portion of each slide upon both sides of a fixed line. The
said opening is of such shape as to uncover only the figures or such portions of the
whole set of slides as are necessary to be read in performing ordinary calculations,
and the opening has at the bottom greater width on the left hand side while from
this point the opening regularly increases in width upwards to the top slide, on the
left hand side of the line. On the face of the board to the left of the top plate are
transverse parallel lines forming a scale set at equal distance apart and numbered
from 1 to 9 inclusive; and each slide, has its face divided by parallel cross lines
into spaces of equal size, of which any five correspond in width to the distance
between any two lines of the scale.
The machine herein described having six slides will perform calculations of
figures to the sixth place in one hundred thousands, and the slides are designated
by a scale along the inner edge of the top plate.
The lowermost slide is appropriated for units and is marked 1 the second 10, the
third 100 and so on to the topmost slide 100000.
The several slides are marked on their spaces according to that percentage or
rate on the $100, upon which all the calculations to be performed by the machine
are based. The rate taken for the machine described is $1.45 on the $100 and the
slides are marked as follows.
Draw out all the six slides until their pointers register with line "1" on the
board then on the third or hundred slide mark the figures 145, in the space
exposed through the opening, in such position that the figure 1 shall lie on the
left of the line, and the figures 45 on the right.
"
The second or "tens" slide will have the same figures repeated but in suitable
position to bring the first figure "1" one space further to the right or in the cents
column, and in the same manner repeating the rate 145 on the first slide. Upon
the remaining slides above the " "hundreds or third slide the rate figures are
marked in such order that they advance one space to the left of the line for each
slide in succession, this being equivalent to multiplying the rate figures by 10 for
each slide.
After these figures are so placed the amount representing the tax on $200 at the
same rate is obtained by calculating and then marked on the hundreds or third
slide in such position that when the slide is drawn out to line 2 the figures
showing this amount will be visible in the opening and in position as required on
the proper sides of the line to divide the dollars and cents.
"
In this case the figures. required are 29 and these are repeated upon all the
slides, but with such change in position that they advance one space to the left in
succession on those slides above the third one, and are moved one space to the right
or decreased by ten below it. And in like manner the amount on each succeeding
hundred is first calculated for the sums represented by the remaining Figures of the
lines on the, board first for the third or bundreds slide, and then properly
marked and located on the other slides above and below. Thus will be obtained for
each slide the numbers 145 29435 58725 &c representing the amount of tax $100
$200 $300 $400 $500 &c and being arranged upon the several slides as before
explained the amount of tax at the rate of 145 on the hundred which is required
on any given sum from one cent up to six places of figures will be shown
through the opening. To find for example the tax on 85-45500int- the rate of 145
on the 100 the fourth or "thousands" slide is drawn out to the line 5 on the

page_text: board, the third slide to the fourth line, and the second and first slides to the
fifth line. The several sums shown on the slides in the opening are then to be
added viz
72:50
1
79-097
which is the amount of tax on the given sum.
The row of figures upon the top face is printed or suitably marked on a strip of
paper which is then fixed to the metal along the row of perforations.
Bated this 3rd day of November 1885.
HASELTINE, LAKE & Co.,
For the Applicant.
COMPLETE SPECIFICATION.
Improvements in Calculating and Adding Machines.
I, EDWARD HALSEY of San Jose in the County of Santa Clara and State of
California, one of the United States of America, Accountant do hereby declare
the nature of my invention for " IMPROVEMENTS IN CALCULATING AND ADDING
MACHINES and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
"
This invention relates to machinery or apparatus for multiplying, dividing, and
computing taxes and percentage, and adding columns, of figures; and it consists
essentially in the combination of a plate provided with a series of slots or openings
and a number of slides, and in certain arrangements of figures all as hereinafter
described.
In the accompanying drawing
Figure 1 is a top view of my machine for multiplying and dividing, with all the
slides in position ready for use.
Figure 2 is a top view of the device for adding columns of figures.
Figure 3 is a top view of the percentage calculating device.
Figure 4 is a cross section of the 3 tables on the line xx.
Figure 5 shews the position of the slides and their numbers in working examples
given in the description as illustrations.
Figure 6 is a view of a portion of one of the slides of the adding table.
Figure 7 is a view of a portion of one of the slides of the percentage table.
,

page_text: In the device for multiplying and performing similar arithmetical calculations
shewn in figures 1, 4 and 5.
*
A represents a board or tablet forming the base of the machine, and B & top
plate which covers the face of the board, excepting the portion A* at one end
where certain indicating lines and figures are located.
:
The plate B while being firmly secured in place, is set clear of the face of the
board, in order to leave a space or way for a number of slides CC; and this space
is divided by means of the pins d d into separate passages across the board, into.
each of which a slide is held and guided. These slides move easily to and fro in
these guides from the left hand end of the board, and they are turned up at this
end to form stops and finger pieces C*. At this end also is an index point or
line C that is used for setting the slide to the required lines of an indicator E, on
the board, in the operation of making a calculation.
The lines of the table or indicator E are spaced as shewn, and are numbered
from 1 to 8 inclusive, beginning at the end nearer the edge of the plate B, these
numbers being placed at the top and bottom.
Each slide is likewise divided by transverse parallel lines into spaces of equal
width, and when any number of slides is set to the lines of the indicator E, the
spaces on the slides will register and be in direct line over one another.
In the top plate B are formed rectangular openings b, b ten in number, each of
suitable width to uncover and expose eight of the spaces on each slide, and of such
length that such portion is exposed on the whole nine slides; nine of these spaces
are designated by numbers from 1 to 9 inclusive, the tenth and last opening not
being numbered with them, as it is employed for calculating interest and is not
used in connection with the indicator E and the other openings, except in working
such examples.
Operations in multiplication and division are performed only with the other.
nine spaces.
Each slide is designated by a number placed at the edge of the top plate B,
beginning with number "1" for the lowest slide and ending with number "9" at
the top one.
In the machine described the indicator E and the spaces appropriated to each
opening 6 one arranged to perform calculations in figures covering eight places
or up to ten millions, the extreme right hand line on the indicator E and the
extreme right hand space on each slide in each of the openings b, being units, the
next one tens, and so on to the eight places.
The slides are numbered in these spaces in the following manner; the unit
spaces on the first or lowest slide seen at the extreme right throughout the whole
number of nine spaces b shew the several products obtained by multiplying the
number of the slide by the number designating the opening, and thus in opening
"1" is seen the number "1," in opening 2 the number 2, in opening 3 the number 3
and so on, one being the product of the slide number multiplied by the opening
number. In the same manner slide number 2 is provided with the numerals 2, 4,
6, 8, 10, 12, 14, 16, 18 exhibited in the openings b from left to right, slide 3 with
the numerals 3, 6, 9, 12, 15, 18, 21, 24, 27, and in the same manner throughout the
remaining six slides.
These slide numerals are in a vertical column along the right hand edge of
each opening b, when the points C³ of all the slides are set to register with line 1
on the indicator E.
The opposite ends of the slide that work in connection with the tenth opening bª
are covered by the plate B when the slides are thus set, but are divided into spaces
which are marked as follows; on the end of the slide 1 the figures 277777; on
slide 2 the figures 555555; on slide 3 the figures 833333; on slide 4 the figures
11, 11, 11; and on slide 5 the figures 1388888. The remaining slides carry the
following figures respectively; slide 6 the figures 1666666; slide 7 the figures
1944444; elide, 8 the figures 2222222; and slide 9 the figures.2499999...

page_text: "
These figures represent decimally the interest at one per cent per year of
365 days for one day on the number of dollars represented by the slide number.
The space uncovered by the opening b* is divided into two parts by a thread
or wire g stretched perpendicularly across it, and which marks the division between
dollars and cents in the row of figures on each slide in the various operations
performed where this space is employed.
•
The operation of the machine in multiplying figures will be understood by
performing the following example, viz, by multiplying 219375 × 349.
Now as the multiplicand contains figures to the sixth place or to hundreds of
thousands and the first figure to be multiplied is 2, the slide corresponding to that
number is drawn out to the thousands place, or until its points C³ register with
line 6 of the indicator E; the first slide is drawn out to the fifth place or line ;
the ninth slide is set to the fourth place; the third slide to the third place; the
seventh slide to the second place; and the fifth to the first or units place on the
indicator E. Then from the opening 3, 4, & 9 in succession are taken the sums.
that will be obtained by adding up the several columns of figures exposed, the
numbers of the openings thus taken being those of the multiplier given, and
resulting sums will be as follows.
From opening 3 the sum 658125 which results from the adding of several figures
:
gives the product required..
The operation of division is simply the reverse of that required in multiplying,
the slides being set in the same manner with reference to the lines of the indicator E
to give the figures of the division and then by examination of the figures seen in
the openings b the sum that can be found the nearest to the dividend taking as
many figures thereof as the divisor is seen to go into it, is ascertained, and the
number of the opening in which this sum is found will be the first figure for the
quotient.
This sum being subtracted and a new dividend formed in the usual manner, the
openings b are again examined to obtain in one of them the sum nearest to that of
the new dividend, and when found the number of the opening 6 shews the second
figure of the quotient, and so on until the example is finished.
'
The method of calculating interest by means of the machine is based on the
principle of finding the amount which in one day at one per cent per year will
produce the same amount of interest as a given sum at a given rate for a given
time will produce, then by setting the slides to the lines of the indicator E
according to the sum ascertained the given interest will be the sum of the figures
exposed to view in the last openings 6°.
The figures shewn to the left of the line g are dollars, and those on the right are t
cents and decimal parts.
The following example in simple interest will illustrate the mode of operation to
find the interest on $625 at 3 per cent for 3 months 27 days.
+
This will be equal to $1875 at 1 per cent for the same time or 117 days, or
1875 x 117..will be interest at one per cent for one day on 219375. Having set 5

page_text: the slides from 6 to 1 inclusive to register with the lines 2, 1, 9, 3, 7, 5 respectively
on the indicator E the following figures will be exposed in the opening b*.
249
which is the required sum of $6.09 the interest on $625.00 for the given time.
In the device for adding columns of figures in Figures 2, 4 and 6, A represents a
board or tablet having a top plate B fixed to and over its upper face, in such
a manner that a small space is left between the plate and tablet to admit a metal
slide C. By means of wire pins d, d, driven through the top plate firmly into the
board beneath at intervals apart crosswise, and in several sets lengthwise of the
board, this space is divided into grooves, the number of which will depend upon
the number of slides used. Each slide C being held and guided by the pins is
easily moved out from under the top plate, and is confined between these guides so
as always to hold its position in line with a slot or long opening b, in the top plate
through which is exposed a portion of the face of the slide beneath.
The machine represented in the drawing has the capacity of adding any number
of figures together as high as 250 in a single column, and for convenience in
manipulating as well as for general compactness in form and size these numbers
are distributed among five slides each carrying fifty numbers.
On the first slide are marked the numbers from one to fifty inclusive, on the
second from fifty-one to one hundred inclusive, and so on through the remaining
slides.
These numbers are arranged along the face of the slides and at regular distances
apart along one side of the middle from end to end, each number being immediately
opposite a circular hole C, so that the slide has, in addition to the line of figures,
a row of holes or perforations as many in number as there are numbers placed on
the slide. This row of perforations is arranged in line along the left side of the
slide from end to end. Each slide therefore contains fifty of such perforations
suitably numbered in regular order.
To each slide also the top plate forms a cover and screen, except for that portion
visible through the slotted opening b, and the length of this slot is made equal to
the space taken up by nine of the spaced perforations, C, so that nine of the.
perforations are exposed to sight, the remaining surface of the slide including all
the numbers as well being covered by the top plate B. The slides are turned
up at the ends to furnish stops C* by which the slides are kept from being moved
too far under the top plate.
These turned up ends also form finger pieces for convenience of moving the slides
when desired to do so by hand.
At each slot or opening b, is marked a scale E, consisting of the nine digits
beginning with number one at the top and ending with number nine at the bottom,
the intervals between the numbers being made to correspond with those between
the perforations. Thus each of the nine perforations seen through the slot b, is
identified by a number on the row of digits along the slide.
The operation of these parts as thus constructed and combined will be best
understood by showing the manner of performing an example in addition of a
single column of figures, and as an illustration the following figures may be taken
to find their sum, viz:-4, 6, 5, 3, 8, 6, 5, 8, 9, 7, 2, 5, 4, 3.
The slides are moved by inserting the end of a style or pencil into the perforations
in the slide opposite those numbers of the row of digits of the scale E corresponding
to the numbers required to be added one at a time the slide being moved outwards,
each time until the pencil strikes the head of the alot.

page_text: "
Into the perforation exposed through the slot b, directly opposite the number "4
and corresponding to the first number in the example, place the point of the pencil,
and push out the slide until the pencil is stopped by the head of the slot: then,
removing the pencil point, place it in the perforation opposite "6" of the scale E,
and proceed in like manner to take each number of the column from the scale E,
until the number is reached, when it will be found that the second slide must be
brought into service because the sum produced by adding the 9 to that already
obtained will exceed the capacity of the first, slide by 4.
When a machine is formed of longer slides however a greater number of figures
may be carried on each slide.
In this case the example requires the second slide, upon which the remaining
figures are worked in the same manner one after the other, by placing the pencil
point into the perforations in succession, opposite the numbers as taken from the
scale E
When the last figure is taken from the scale E and the slide moved by the
pencil, the aggregate will be shown by the highest number that is exposed on the
slide at the end of the top plate, and in the case of an example requiring two or
more slides to be used, then the last slide will show the required amount.
In constructing these slides I have made them of strips of thin sheet metal, with
the perforations C punched through the strips and of a backing afterwards fixed
upon the bottom or lower face to prevent the point of the pencil or other
instrument from scratching or marking the board beneath.
In the device for computing taxes and percentage in Figures 3, 4 and 7,
A represents a suitable board or tablet forming the base of the machine and B a
top plate covering about one half of the surface and also raised above this covered
portion sufficiently to afford a space or way for a number of slides C C.
By means of the pins d d placed in rows across the board, this space is divided
into separate grooves to hold and guide the slides which are fitted to move easily
in and out under the plate.
The end of each slide is turned up to form a stop C* that serves also for a finger
piece to work the slide.
At the inner edge of the top plate B is an opening 6, of peculiar shape that
uncovers and exposes to view a portion of each slide upon both sides of a fixed
line g.
The object of making the opening of the peculiar shape shown in Figure 3 is for
the purpose of uncovering only the figures or such portions of the whole set of
slides as are necessary to be read in performing ordinary calculations, and the
opening has at the bottom greater width on the right of the line g, while from this
point the opening regularly increases in width upwards to the top slide, on the left
hand side of the line. On the face of the board to the left of the plate B, are
transverse parallel lines forming a scale E, set at equal distances apart and
numbered from 1 to 9 inclusive; and each slide C has its face divided by parallel
cross lines C into spaces of equal size, of which any five correspond in width to
the distance between any two lines of the scale E
The machine herein described having six sides will perform calculations of figures
to the sixth place in one hundred thousands, and the slides are designated by the
scale seen at f, along the inner edge of the top plate.
The lowermost slide is appropriated for units and is marked 1, the second 10,
the third 100, and so on to the topmost slide 100,000.
The several slides are marked on their spaces according to that percentage or rate
on the $100, upon which all the calculations to be performed by the machine are
based. The rate taken for the machine shown in the drawings is $1.45 on the $100
and the slides are marked as follows:-
Draw out all the six slides until their pointers C³ register with line "1" on the
board, then on the third or hundred slide mark the figures 145, in the space exposed
through the opening b, in such position that the figure 1, shall lie on the left of the
Line, g, and the figures 45 on the right,

page_text: The second or "tens" slide will have the same figures repeated, but in suitable
position to bring the first figure "1" one space further to the right or in the cents.
column, and in the same manner repeating the rate 145 on the first slide. Upon
the remaining slides above the "hundreds" or third slide the rate figures are
marked in such order that they advance one space to the left of the line
each slide in succession, this being equivalent to multiplying the rate figures by 10
for each slide.
for
After these figures are so placed the amount representing the tax on $200 at the
same rate is obtained by calculating and then marked on the hundreds or third
slide in such position that when the slide is drawn out to line 2, the figures showing
this amount will be visible in the opening b, and the position as required on the
proper sides of the line g, to divide the dollars and cents.
In this case the figures required are 29 and these are repeated upon all the slides,
but with such change in position that they advance one, space to the left in
succession on those slides above the third one, and are moved one space to the
right or decreased by ten below it. And in like manner the amount on each
succeeding hundred is first calculated for the sums represented by the remaining
figures of the lines E first for the third or hundreds slide, and then properly marked
and located on the other slides above and below. Thus will be obtained for each
slide the numbers 145, 29,435, 58,725, &c., representing the amount of tax $100
$200 $300 $400 $500 &c and being arranged upon the several slides as before
explained the amount of tax at the rate of 145 on the hundred which is required
on any given sum from one cent up to six places of figures will be shown through
the opening b.
To find for example the tax on $5.455 at the rate of 145 on the 100, the fourth
or "thousands" slide is drawn out to the line 5 on the board, the third slide to
the fourth line, and the second and first slides to the fifth line.
The several sums shown on the slides in the opening are then to be added, viz:-
which is the amount of tax on the given sum. The row of figures upon the top
face is printed or suitably marked on a strip of paper which is then fixed to the
metal along the row of perforations.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to me
by ny foreign correspondent I declare that what I claim is
First In a device for multiplying and performing similar arithmetical calculations,
the combination of the frame composed of the board A and top plate B, the former
having the table of lines and numbers E, and the latter the openings b, beach
designated by a number, and the numbered slides C, C, having their surfaces spaced
and marked with figures which are obtained by multiplying the number of the
slide successively by the several numerals designating the openings, the products of
such multiplication being placed in said openings, substantially as described, for
operation as set forth.
Second-In a machine of the character described, the numbered slides C, C, each
of which has its face divided in spaces by lines, into which spaces are placed
numbers that are obtained by multiplying the designating number of the slide by
the numerals from 1 to 9 inclusive in succession, the said slides being arranged for
operation with reference to a plate B having openings 6, equal in number to the
numerals. taken for multipliers, as set forth.
Third-The combination of the plate B having the opening 6* and the line
wire 9 of the slides O, O, numbered from 1 to 9 inclusive and adapted to be moved

page_text: "
back and forth beneath said opening and having on the end portion beneath said
plate numbers which represent the interest at one per cent for one day, (or from $1
to $9 inclusive) and the table E at the opposite end, for operation as set forth in
Figures 1, 4 and 5.
•
Fourth In a device for computing taxes and per centage, the combination of
the board A. its top plate B; the irregularly shaped opening b. in the top plate
haying the line g, thread or wire g stretched across it; the spaced and numbered
lines E on the board A; the slides C adapted to be moved out and in underneath
the top-plate and confined in their movements by pins d, d; and the spaces or
divisions on the upper face of each slide, the said spaces having numbers which are
based in a given rate, and are produced by regularly increasing and decreasing the
same above and below "hundreds" by ten, the same being arranged and applied
for operation as set forth in Figures 3, 4 and 7.
Fifth In a device for adding columns of figures the board or tablet A, the top
plate B, provided with openings and the slides C, C, each provided with the row of
spaced perforations which are numbered consecutively from "i" upwards, the
whole set of slides being also numbered consecutively and in progression from the
first to the last one, the row of numerals from 1 to 9 inclusive being placed at each
opening to designate the perforations exposed for operation as set forth.
Sixth In an adding machine of the character described, the slide C having the
row of perforations and the column of Figures corresponding therewith arranged in
regularly increasing order, substantially as described, for operation with a fixed
plate B having an opening 6 as set forth with reference to Figures 2, 4 and 6.
Dotad this 2nd dor of Avant 1886