US1228385A - Calculating appliance. - Google Patents

Description

P. B. ARRINGTON 6/, C. H. MILLER.

CALCULATING APPLIANCE.

APPLICATION FILED APR. 10. 1916.

Patented June 5, 191.

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UNITED STATES PATENT OFFICE.

PERRY B. ARRINGTON AND CHARLES H. MILLER, OF CHICAGO, ILLINOIS, ASSIGNORS TO MULTICALCULATOR COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELA- WARE.

CALCULATING APPLIANCE.

Patented June 5, 1917.

Application filed April 10, 1916. Serial No. 90,112.

To all whom it may concern:

Be it known that we, PERRY B. ARRING- TON and CHARLES H. MILLER, both citizens of the United States, residing at Chicago, 1n the county of Cook and-State of Illinois, have invented certain new and usefulImprovements in Calculating Appliances, of which the following is a specification.

Our invention pertains to calculating machines and relates more especially to appliances of this general character adapted for multiplication and division.

Its leading object is the provision of a device of this kind wherein one of the numbers entering into the multiplication, as for instance, the multiplicand, may be set up or registered on one or more keys of a bank or banks of keys of graduated numerical values and the product determined by turning one or more cylinders to bring the particular multiplier of a row or series of such figures to a. definite position, the product being indicated by the key or keys in cooperation with the cylinders.

A further purpose of the invention is the production of a machine of this character wherein it is possible for a comparatively inexperienced person by a simple operatlon to make any calculation in multiplication, and, in most cases, this may be accomplished with not more than one manipulation or movement of each cylinder.

An additional feature of the appliance resides in providing the cylinders with special multiplication factors or multipliers which are present in the rows of multipliers of the cylinders, whereby various desired results may be quickly and readily determined, such for example, as taking off the most commonly used chain discounts with one operation, computing gross profits on sales, extending invoices, reducing gross, dozen, bushel, etc, to any fractional part thereof, pro-rating premium on canceled insurance policies, the selling price of goods to effect a Figure 1 is a fragmentary or'broken partial elevation and partial section of the appliance;

Fig. 2 is an enlarged cross-section through the upper portion of the device;

Fig. 3 is a fragmentary longitudinal section on line 33 of Fig. 2'

Fig. i is a section of the portion of the structure shown in Fig. 3;

Fig. 5 is a similar detail of the locking mechanism for the outer cylinder;

Fig. 6 is a partial showing of the colum- .nar sheet of figures or values constituting the covering for the outer cylinder; and i Fig. 7 is a similar view of the covering sheet for the inner cylinder.

By reference to the drawings, it will be observed that the appliance includes an inclosing housing or casing 8, mounted to rest on suitable feet 9, such casing containing two cylinders or drums 10 and 11 concentrically arranged one within the other and revolubly supported in the ends of the easing by means of trunnions and sleeves 12 and 13, or in any other approved manner. At the left-hand end of the device the shaft of the inner cylinder is extended through the housing, its protruding portion being provided with a suitable knurled hand-wheel It, the hollow sleeve or shaft of the outer cylinder being similarly equipped with a somewhat larger hand-wheel 15, whereby the cylinders or drums may be independently rotated manually at will.

The upper portion of the casing is provided with a flat inclined face 16 equipped with an elongated horizontal window 17 disposed longitudinally of the housing and through the glass of whichthe figures on thecylinders or drums are readily visible. Below the window the appliance is supplied witha bank orv group ofnumber or value finger keys, 18, similar to those of a type- .writer, which in .un-actuatedposition, that is, 111 normal condition, stand substantially upright as shown in Fig. 2. Above the win dow 17 the device has a somewhat-similar bank or series of value keys 19, which in unoperated condition are inclined, as shown in Fig. 2. As is clearly illustrated in Figs. 1 and 2, each bank or group consists of two rows of keys in staggered-relation so that a greater number of keys may be grouped together in a minimum of space.

The lower bank or group of keys is adapted to cooperate with the outer of the two cylinders in a manner hereinafter indicated, and the keys bear printed characters or numbers arranged according to their numerical value. Stated somewhat differently, the keys of the lower bank have printed thereon the fractions 1/8, 3/8, 5/8, 7/8, 1/6, 5/6, 1 5, 2 5, 3 5, 4 5, 1 1, 3 1, 1 3, 2 3, and

1/2, and also all of the integers or integral numbers from 2 to 43 inclusive, all arranged in sequence according to their numerical values.

The upper group of keys is adapted to coact with the inner of the two cylinders and each of these keys displays a number, these numbers being in order and ranging from 14 to 99 inclusive, so that the values expressed by the upper keys form a direct extension or continuation of those of the lower keys. The numbers printed or displayed on the keys of both groups we may designate, for the sake of explaining the operation of the machine, as the multiplicands.

Referring again to the lower bank of keys, it will be noticed that these are pivoted at 20 and 21 on suitable rods supported by ribs 22 on the upper face of a plate or bar 23 apertured at 24 for the accommodation of the bent ends or shanks of the keys. The under face of the bar 23 is grooved at intervals at 25, 25, for the reception of the alter nate sliding plates 26, 26, the similar intermediate slides 27, 27, bearing against the under faces of the ribs of the member 23 between the cavities 25. In order to hold these sliding members properly in position, a plate 28 is secured by screws to the member 23, below them, and on its upper face it is supplied with a plurality of bosses 29 and 30 fitting in grooves of the slides to guide them in their movements and limit the extent of their actuations. Each slide is apertured as at 31, (Fig. 2), for the reception of the lower end of the corresponding key-shank 18. It should be clear, therefore, that each of the keys 18 is associated with one of the slides 26 or 27 and that a downward rocking of the key will cause a corresponding upward sliding of the plate. The upper end of each of these overlapping sliding members is provided with an aperture or window 32 for a purpose hereinafter designated, constituting an index or marker for cooperation with the numbers appearing on the outer cylinder. At the longitudinal center or middle of the appliance there is a fixed immovable marker 33 on bar 23 whose upper edge is in alinement or register with the edges of the unactuated indices of the keys 18, as is clearly shown in Fig. 3. These keys and their slides are so balanced or related that after a key is rocked down it maintains such position until manually shifted up again to normal or neutral position.

The pivoted keys of the upper bank or group are similarly individually associated or joined with a sliding member 31, but these keys 19, as will be readily understood, are rocked upward when they are actuated instead of being shifted downward as are the keys 18. The lower edges of the members 31 constitute the markers or indices, these slides not being equipped with windows or openings as are the lower slides of the other bank of keys. These keys also maintain their shifted positions when operated until they are intentionally reset. There is be sides a fixed marker 34c in alinement with the row of multipliers of this inner cylinder.

Turning now to the outer cylinder 10, it will. be observed that this is equipped with a slot or narrow window extending the full length of the drum, and it will be noted furthermore that in order to maintain the cylinder in a position with the part 35 in register with the window 17 a locking member 36 (Fig. is provided which is fulcrumed on the inner side of the end of the casing at 37 and is supplied with an actuating spring 38 tending to force its tooth or finger 39 into a recess 40 of such outer cylinder. At the left-hand end of the housing a handle 11 is provided which is secured to the locking-lever 36 to permit the retraction of the locking tooth when desired.

This external cylinder has mounted on its outer cylindrical surface a columnar chart of figures arranged in rows circumferentially around the cylinder and also longitudinally thereof. Such chart 12 is shown fragmentarily in Fig. 6 and by reference to such figure it will be seen that the middle row of figures 13, which extend circumferentially around the drum or cylinder, constitutes a series of multipliers, preferably printed in a color different from the other figures of the chart, as for instance, in red. At the top of this row is the smallest multiplier 1/6 whose decimal value, .06-1/4, is also indicated in the column. 7 Below this is a series of other fractions, preferably, though not necessarily, arranged according to their numerical values, and each desirably having its decimal equivalent specified. These fractions include sixteenths, twelfths, ninths, eighths, sevenths, sixths, fifths, thirds, fourths. and a half, and range from 1/16 to 8/9. Below the latter, the column continues with the numeral 2 and contains all of the integers up to and. including 99, and also additional numerals like 69-1/4, 76-19/20, 92-3/20, 95-1/16, for a reason specified below. Also in this column the numbers run from 105 to 1005 by tens, being multiples of 5, thus: 105, 115, 125, 135, including besides, such numbers as 144, 208, 274, 729, 873. 882, 931.

This middle column of multipliers is in register or alinement with the fixed marker 33 and on opposite sides of it there are columns of figures extending circumferentially around the cylinder in number and in position corresponding to the keys and the values of the keys of the lower bank, a portion only of such rows being shown in Fig. 6. Stated somewhat differently, and by way of illustration, the left-hand key of the lower bank is 1/8 and the figure at the top of the left-hand column of the chart is .008, representing the product of 1/16 and 1/8. Each one of these numbers in any of the columns represents the product of the corresponding multiplier in the longitudinal row on the chart and the value of the corresponding key of the lower bank. For instance, the next to the end key at the righthand of the bank is 42, the figure in the next to the last row of figures on this chart and corresponding to the multiplier 3 is 126 representing the product of 42 and The lower portion of this chart contains three tables; that at the left, 44, represents discounts and gives the decimal number by which a multiplication should be made in order to secure a chain of discounts of certain percentages. For example, a discount of 3% and 2% would indicate that the price should be multiplied by .95-1/16 and for a discount of 10%10%-10%-5%, the corresponding multiplier should be .69-1/4.

The middle table 45 of the three represents the interest on various sums for one day and is tabulated according to the interest rates from 4 to 8 per cent, which row of rates on the chart is directly beneath the column of multipliers above described.

The right-hand table 46 presents the multipliers to be used in effecting profit computations showing that to figure a gross profit on sales the cost price should be marked up the corresponding cost price percentage indicated. For example, if there is to be a gross profit of 10% on the sales the cost price should be marked up 11-1/9%, or it may be expressed as the fraction 1/9.

. The chart 50 on the inner drum or cylinder is illustrated fragmentarily developed in Fig. .7. It has a middle column of red multiplier figures 51 exactly like those of the chart on the 'outer cylinder shown in Fig. 6, but the product figures in the other columns on both sides of the multiplier column are difi erent because this chart cooperates with the upper bank of keys which are of higher values than those of the lower bank. For example. the product of 98 and 105 will be found in the column on the chart corresponding to the 98 kev and in the row on the line of 105. being 10,290.

At the bottom of this chart there are seV eral tables 52, 53, 54, 55, 56, and 57. Tables 52, 53, and 54 give the reciprocal or multiplier to be used in connection with calculations for different numbers: of hours per week. For instance, if a man earns certain wages for a weeks work of 54 hours, the amount of his wages for two hours will be determined by multiplying the amount of his weeks wages by the number .037 found in table 53. The reciprocal of 144 (gross) and its multiples are found in table 55. The reciprocal of 365 (days per year) and itsv multiples are found in table 56, and various miscellaneous reciprocals or multi pliers are found in table 57.

The appliance is operated substantially as follows:

Example No. 1: Let us assume that it is desired to multiply 23 by 47. The operator depresses the key 23 of the lower bank, which automatically raises the windowed shutter or index 26 or 27, as the case may be. He then turns the outer cylinder until the numeral 47 in the middle row of figures, which of course, is the column of graduated multipliers, is just above the fixed marker or 33. The product 1081 is read through the aperture of the index of the key.

Example No. 2: If it is required to multiply 3213 by 97 the attendant depresses keys 32 and 13 both of which are in the lower bank or group. This operation, of course, elevates the indices or markers 26 or 27 and at the same time registers this multiplicand on the machine, because the keys stay depressed and the markers remain raised. The outer cylinder is now rotated to bring the multiplier 97 to marker 33. The product visible through the window of the index of key 32 is 3104 and since 32 was in the hundredths place of the number 3213 two ciphers are annexed to this product, making it 310,400, which is noted on a memorandum pad. The product indicated by the index of key 13 is 1261 and since this'was in the units place in the original number 3213 no ciphers are aflixed. This amount, 1261 is written down on the pad beneath the number 310,400, and the two added together, giving the answer, 311,661.

Example No. 3: Multiply 86 by 45. The key 86 of the upper group is rocked up, which lowers its index or marker 34. Since this bank of keys coiiperates only with the inner cylinder, the outer cylinder is brought to neutral or locked position with its slot or window 35 in register with the window 17 of the housing or casing. Then the inner cylinder is turned to bring the multiplier 45 of the row 51 of figures between the fixed marker 34 and the lower edge of the slot of the outer cylinder. Now the product 3870 may be read just below the index of key 86.

Example No. 4: Multiply 2872 by 56. To solve this problem the key 28 of the lower bank should be pushed down and the key 72 of the upper series shifted upwardly. The product indicated by the key 28 with 56 as a multiplier should be read from the outer cylinder and two ciphers added,

thus156,800, and then the product determined by key 72 on the inner cylinder should be read and added to the 156,800, tl1us156,800+4032=160,832.

Example No. 5: Multiply 597 by 438. Inasmuch as there is no multiplier 438 in the multiplier column of either cylinder the an swer is determined by multiplying 697 by 435 and multiplying 697 by 3 and then adding the two products together.

Example No. 6: Multiply 3142 by 2327. First multiply 3142 by 2300 using 23 as the multiplier and adding two ciphers, thus, 7,226,600. Then turn the outer cylinder to 27 and multiply 3142 by 27 adding this, 84,834, to the other product, giving the answer 7,311,434.

Example No. 7: Multiply 4275-1/6 by 7/12. To determine the answer, the attendant manipulates the keys 42, 75, and 1/6 respectively, this operation placing or registering the amount on the machine. The outer cylinder is then turned until the indicator or marker designates 7/12 in the multiplier. The product visible through the window of the index of key 42 is 24.5 and by adding two zeros or ciphers and moving the decimal point two places to the right, the result is 2450. The product visible through the window 1/6 is .097. Then the outer cylinder is turned until it looks with its opening or slot in register with the casing window so that the index of the key 75 may be used in connection with the inner cylinder. Such inner cylinder is now turned until the marker specifies 7/12 in the multiplier column and the product designated by the marker of key 75 is 43.75. Adding together 2450+.097+43.75 gives the total 2493.847.

To illustrate the use of the machine in connection with chain discounts and profit systems, we will assume the following examle. p Example No. 8: An invoice'indicates a list price of articles as $17 .50 per gross less a discount of 10%10%10% and 5%. Find the net cost of each article and the selling cost of each in order to make a gross profit of 33-1/3% on the sale. The example is solved in the following manner. The outer cylinder is turned to the table of discounts and it will give the amount as .6925 or .69-1/4 on $1.00 as corresponding to the discount of 10%10%10%5%. $17.50 is then multiplied by .69-1/4. This is done by operating the keys 17 and 1/2, placing this multiplicand on the machine. The outer cylinder is turned until the indicator designates 691/4 in the multiplier column. The amount visible for the key 17 is 1177 -1/4 and the product visible for 1/2 is 34-5/8. These are added together and we point ofl two decimal places as per instructions in decimal fractions, giving a total product of 12.11-7/8 or 12.11875. This is the cost per gross and in order to secure the cost of each article we divide by 144 or the problem may be stated thus: divide $12.11-7/8 by 144. To do this the outer cylinder is locked with its window in register with the casing window and the inner cylinder is turned to the tables of reciprocals. It will be noticed that the reciprocal of 144 is approximately .00695, or, stated differently, to divide $12.11-7/8 by 144, this sum is multiplied by .00695. Keys 11 and 12 and 7/ 8 in the multiplicand are operated, the outer cylinder is turned until the indicator designates 695 and the product through the window of the key 12 is 8340 to which two ciphers are added, making it 834,000. The product at the window of the key 11 is 7645 and the product through the window of key 7 /8 is 608-1/8. Adding these three together and pointing off seven decimal places gives 8.0842253-1/8 so that the price of each article net would be this amount. Then the outer cylinder is turned to the table giving percentages of profit on the sale and its equivalent on the cost showing that to make 33-1/3% on the sale the cost price must be marked up 50%. Then we multiply .0842253-1/8 by 1.5 by operating keys 84, 22, 53, and 1/8. The outer cylinder is looked as per instructions above and the inner one turned until the multiplier 15 is at the indicator. The product of 84 and 15, including four ciphers for thousands, is 12,600,000; the product of 53 and 15 is 795. Both of these amounts are taken from the inner cylinder before the amounts or products are read from the outer cylinder for the sake of convenience. Now the cylinder is unlocked to bring the multiplier 15 into position. The product of 22 times 15 is 33,000 and the product of 1/8 times 15 is 1-7/8. These four products added together, and marking off eight decimal places, seven in the multiplicand and one in the multiplier, gives 12,633,796-7/8 showing that the selling price of each article in order to make 33-1/3% gross profits on the sale is $126.

Example No. 9: As salary is 37-1/2 per hour and his time for a given week is 41 hours and 40 minutes (40 minutes equaling 2/3 of an hour). To determine the total salary due him, multiply 41-2/3 by 37-1/2 in accordance with the principles illustrated above.

Example No. 10: Find the interest on $2000.00 at 5-1/2% for 45 days. Multiply $2000.00 by 45, giving a product of $90,000. Turn to the 90,000 in table No. 45, of the outer cylinder, and at once the interest is found to be $13.75.

For the pro-rating of insurance policies on which premium is charged for one year the amount earned for one day is determined by dividing by 365 or multiplying by the reciprocal of 365 which is approximately .0027 1. This example and all similar examples can be solved with one operation of the device because of the especial arrangement of figures in the multiplier column. That is to say, the figures in the rows of multipliers of the two cylinders are so arranged that any usual commercial calculations can be made with one operation only.

To those skilled in this art, it will be apparent that many minor mechanical changes may be made in the structure set forth herein in detail without departure from the substance and essence of the invention and Without the sacrifice of any of its substantial benefits and advantages. While in this application the movable keys of various values have been designated as representing the multiplicand values and the rows of figures on the cylinders as multipliers, of course, the reverse is equally true. While the charts of figures have been described as secured to the surfaces of the cylinders, it is obvious that the numbers of the charts might be applied directly to the surfaces of the cylinders rather than to cloth or paper covers.

We claim:

1. In a calculating-appliance of the character described, the combination of a manuallyoperable revoluble cylinder displaylng a plurality of rows of numbers on ts surface, said numbers being arranged in rows both transversely and longitudinally of the cylinder, one of said transverse rows bemg a series of multipliers, the other transverserows being products of such multipliers, a plurality of pivoted keys of different multiplicand values, there being one of such keys for each of said transverse product rows,

. each key displaying its value, said keys being manually actuated to operative and inoperative position and maintained in either position until reset, and an index actuated by each of said keys and in cooperative relation with the corresponding product row of numbers on the cylinder, whereby upon actuating any one of such keys corresponding to the proposed multiplicand and revolving said cylinder to bring the proposed multiplier to a predetermined position, the number designated by the index of the actuated key will be the product of such multiplicand and multiplier, substantially as described.

2. In a calculating-appliance of the character described, the combination of a pair of manually-operable independently-revoluble cylinders one Within the other, each of said cylinders displaying a plurality of rows of numbers on its surface, said numbers being arranged in rows both transversely and lon gitudinally of the cylinder, one of said transverse rows being a series of multipliers,

able keys of different multiplicand values one for each of said transverse product rows on the other cylinder, said keys maintaining their actuated positions until re-set, whereby upon actuating any one of such keys corresponding to the proposed multiplicand and shifting the corresponding cylinder to bring the proposed multiplier to a predetermined position, the number opposite the actuated key will be the product of such multiplicand and multiplier, substantially as described.

3. In a calculating-appliance of the character described, the combination of a pair of manually-operable independently-revoluble cylinders one within the other, each of said cylinders displaying a plurality of rows of numbers on its surface, said numbers being arranged in rows both transversely and longitudinally of the cylinder, one of said transverse rows being a series of multipliers, the other transverse rows being products of such multipliers, said outer cylinder having a window for the display of the numerals on the inner cylinder, a plurality of pivoted keys of different multiplicand values, there being one of such keys for each of said transverse product rows of one of said cylinders, each key displaying its value, a second set of pivoted keys of different multiplicand value there being one of such keys for each of said transverse product rows of the other cylinder, each of said keys displaying its value, the keys of both groups being manually actuated to operative or inoperative position and maintained in either position until re-set, and an index actuated by each of said keys and in cooperative relation with the corresponding product row of numbers on the corresponding cylinder, whereby upon actuating any one of such keys representing the proposed multiplicand and turning the corresponding cylinder to bring the proposed multiplier to a predetermined position, the number designated by the index of the actuated key will be the product of such multiplicand and multiplier, substantially as described.

4:. In a calculating-appliance of the character described, the combination of an inclosing casing provided with a window, a pair of manually-operable independentlyrevoluble cylinders in said casing one within the other, each of said cylinders displaying a plurality of rows of numerals on its sur face, said numerals being arranged in rows both transversely and longitudinally of the cylinder, one of said transverse rows being a series of multipliers, the other transverse rows being the products of such multipliers, the outer cylinder having a window for the display of the numerals on the inner cylinder, a series of movable keys of different multiplicand values at one side of said cas' ing window, one for each of said transverse product rows of one of said cylinders, each of said keys displaying its value, and a second series of movable keys of different multiplicand values at the opposite side of said casing window, one for each of said transverse product rows of the other cylinder, each of said latter series of keys also displaying its value, whereby upon actuating any key of either series representing a proposed multiplicand and turning the corresponding cylinder to bring the proposed multiplier opposite the casing window, the number opposite said key will be the product of such multiplicand and multiplier, substantially as described.

5. In a calculating-appliance of the character described, the combination of an inclosing casing provided with a window, a pair of manually-operable independentlyrevoluble cylinders in said casing one within the other, each of said cylinders displaying a plurality of rows of numbers on its surface, said numbers being arranged in rows both transversely and longitudinally of the cylinder, one of said transverse rows being aseries of multipliers, the other transverse rows being products of such multipliers, said outer cylinder having a window for the display of the numerals on the inner cylinder, a series of pivoted keys of different multiplicand values at one side of said casing window, one for each of said transverse product rows of one of said cylinders, a second series of pivoted keys of different multiplicand values at the opposite side of said casing window, one for each of said transverse product rows of the other cylinder, each key of both series displaying its value and maintaining its actuated position until manually re-set, and a sliding index actuated by each of said keys and cooperating with one of the product rows of the corresponding cylinder, whereby by rocking one of said keys of a value of the proposed multiplicand, thus sliding its index, and turning the corresponding cylinder to bring the proposed multiplier to a predetermined position opposite the casing window, the product will be designated by said index, substantially as described.

6. In a calculating-appliance of the character described, the combination of a windowed casing, a pair of revoluble cylinders in said casing one within the other and each displaying numbers on its surface arranged in rows both transverse and longitudinal, the numbers of one of said transverse rows being multipliers, the numbers of the other rows being products, a bank of pivoted keys below said window of different multiplicand values, an index for each of said keys movable upwardly when the key is rocked downwardly, a bank of pivoted keys above said window of multiplicand values differing from each other and from the values of the lower bank of keys, and an index for each of said upper keys movable downwardly when the key is rocked upwardly, whereby by rocking one of said keys of a value of the proposed multiplicand and thus shifting its index and turning the corresponding cylinder to bring the proposed multiplier to a predetermined position opposite the window of said casing, the product will be designated by said index, substantially as described.

7 In a calculating-appliance of the character described, the combination of a revoluble cylinder displaying numbers on its surface arranged in rows both transverse and longitudinal, the numbers of one of said transverse rows being multipliers, the numbers of the other transverse rows bein products of such multipliers, a plurality o pivoted keys of different multiplicand values arranged in a staggered row, and an index slide operatively associated with each of said keys and adapted to cooperate with the numbers of that transverse row corresponding to its key, said slides overlappin one another, whereby by rocking one of said keys of a value of the proposed multiplicand, thus sliding its index, and turning the cylinder to bring the proposed multiplier to a predetermined position, the product will be designated by its index, substantially as described.

8. In a calculating-appliance of the character described, the combination of a casing having an elongated horizontal window, a pair of revoluble horizontal concentric cylinders one inside of the other in said casing and each displaying on its cylindrical surface a plurality of rows of numbers, said numbers being in rows both transverse and longitudinal of the cylinder, one of said transverse rows being a series of multipliers, the other transverse rows being products of said multipliers, said outer cylinder having a longitudinal slot adapted to be brought into register with the casing window for the display of the inner cylinder therethrough, a bank of pivoted keys of different multiplicand values arranged in a staggered row below said window, an index for each of said keys movable upwardly when the key is rocked downwardly, each index cooperating with the numbers of that transverse row corresponding to its key, a second bank of pivoted keys of different multiplicand values arranged in a staggered row above said window, and an index for each of said upper keys movable downwardly When the key is rocked upwardly, each. of said indices cooperating with the numbers of that transverse roW corresponding to its key whereby by rocking one of said keys of a value of the proposed multiplicand and thus shifting its index and turning the corresponding cylinder to bring the proposed multiplier to a predetermined position before the casing Window the product Will be described.

P. B. ARRINGTON. CHARLES H. MILLER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.

designated by said index, substantially as 1'

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