Origin of Modern Calculating Machines A chronicle oi the evolution of the principles that form the generic make-up of the Modern Calculating Machine BY J. A. V. TURCK Member ot The Western Society of Engineers i CHICAGO. 1921 Published under the auspices of The Western Society of Engineers * f * Copyright, 1921, by J. A. V. Turck 438802 Foreword THERE is nothing romantic in figures, and the average man takes little interest in any subject pertaining to them. As a result of this antipathy, there is plenty of historic evidence of man's endeavor to minimize the hated drudgery of calculation. While history shows that, from prehistoric man down to the present age, human ingenuity has turned to mechanical means to overcome the brain fatigue of arithmetical figuring, it is within quite recent years that he has really succeeded in devis- ing means more rapid than the human brain. Of this modern product little has been written, except in disconnected articles that have in no case offered a complete understanding as to who were the great benefactors of mankind that gave to the world the first concrete production of these mod- ern principles of mechanical calculation. The writer, believing that there are many who would be interested to know the true facts rela- tive to this subject, has given to the public, in that which follows, a chronicle of the evolution of the principles disclosed in these modern machines, along with the proofs that form the foundation for the story in a way that all may understand. Although the subject has been handled in a way that makes it unnecessary for the reader to be carried through a jangle of tiresome mechanical construction, the writer believes that there are 1 .'IOkkji,'^ of.' Modern Calculating Machines many interested in the detail workings of these machines, and has for that reason provided an interesting and simple description of the working of each illustrated machine, which may be read by those who wish, or skipped over, if the reader desires, without the danger of losing knowledge of the relation of each of these machines to the Art. Chapters PAGE Foreword 1 Types of Ancient and Modern Machines 5 The Early Key-Driven Art 17 The Key-Driven Calculator 50 Early Efforts in the Recording Machine Art 79 First Practical Recorders Ill Introduction of the Modern Accounting Machine 144 The High-Speed Calculator 149 The Improved Recorder 163 The Bookkeeping and Billing Machine 174 A Closing Word 190 Illustrations PAGE Frontispiece, "Stone Age Calculating" One of the Pascal Machines 10 Photo of Blaise Pascal 11 Parmelee Patent Drawings 16 Hill Patent Drawings 23 Chapin Patent Drawings 28 From the Stark Patent Drawings 32 From the Robjohn Patent Drawings 36 From Drawings of Bouchet Patent 314,561 40 Drawings of Spalding Patent No. 293,809 46 "Macaroni Box" Model 53 Photo of Dorr E. Felt 55 The First "Q)mptometer" 57 From Drawings of Felt Patent No. 371,496 58 Bill for First Manufacturing Tools of the Comptometer .... 68 Early Comptometer 69 Letter from Geo. W. Martin 71 Testimonial 72 Testimonial 73 Letters from Elliott and Rosecrans 74 From Drawings of Barbour Patent No. 133,188 78 From Drawings of Baldwin Patent No. 159,244 83 Baldwin Machine 83 From Drawings of Pottin Patent No. 312,014 88 From Drawings of Burroughs Patent No. 388,118 94 Photo of Wm. S. Burroughs 95 Drawings of Ludlum Patent No. 384,373 104 From Drawings of Felt Patent No. 405,024 112 Testimonial 117 Felt Recording and Listing Machine 118 From Drawings of Felt Patent No. 465,255 121 Felt Tabulator 126 One of the Early "Comptographs" 130 Photo of Gottfried Wilhelm Leibnitz 132 Leibnitz Calculator 133 From Drawings of Burroughs' Patents Nos. 504,963 and 505,078 136 Burroughs' Recorder 137 From the February 1908 Issue of Office Appliances Magazine 142 The High-Speed Calculator 148 Two Pages from Wales Adding Machine Co. Booklet 165 Moon-Hopkins Billing and Bookkeeping Machine 176 Napier's Bones 179 From Drawings of Barbour Patent No. 130,404 180 Photo of John Napier 181 From Drawings of Bollee Patent No. 556,720 186 4 The Modem Accountinjy Machine THE tenn "adding machine" or "calculating machine" to most of us represents the ma- chine we have seen in the bank. The average person is not familiar with the different types of accounting machines, to say nothing of the many uses to which they are put; but he has a vague idea that to hold any value they should produce a printed record, he doesn't know why and he hasn't stopped to reason why; but those he has seen in the bank do print, and any machine the bank uses, to his mind, must be all right. There are, of course, people who do know the different types of accounting machines, and are familiar with their special uses, but there are very few who are familiar with the true history of the modern accounting machine. Articles written by those not familiar with the true facts relative to the art of accounting ma- chines have wrought confusion. Their errors have edge lacking been copied and new errors added, thus increasing the confusion. Again, claims made in trade adver- tisements and booklets are misleading, with the result that the truth is but little known. These facts, and the psychological effect of see- ing a certain type of machine in the bank would lead the average man to believe that the recording- adding machine was the only practical machine; Ceneral knowl- Origin of Modern Calculating Machines and also (as someone stated in the December, 1915, issue of the Geographic Magazine) that Burroughs was the inventor of the recording-adding machine. Although the history of accounting machines dates way back into the tenth century, the modern accounting machines are of quite recent origin, and are especially distinguished by the presence of depressable keys. The keys in these machines act as a means of gauging the actuation which determines the value in calculation, whether the machine is key-driven or key-set with a crank or motor drive. These modern machines, which come within the classification of key-driven and key-set, have their respective special uses. Key-driven The key-driven machine, which was the first 'f /fc'*'"^'.'^'^ produced of these two types of modern machines, machinrs does iiot print, and is used for all forms of calcu- lation, but is generally behind the scenes in the accounting rooms of all lines of business, and for that reason is not so well known as the key -set crank-operated or motor-driven machine, which is designed to print and is always in full view in the bank where it is used to print your statement of account from the vouchers you have issued. When we stop to analyze the qualities of these two types of machines, we find that each has its place and that neither may truly serve to displace the other. The organization of each is designed with reference to the special work it was intended to do. The calculating machine, having only to perform the work of revolving the numeral wheels in calculating addition, subtraction, multiplication and division in its many forms and combinations, Types of Ancient and Modern Machines may be key-driven (on account of the slight mechanical resistance met with in action), and thus, as a one-motion machine, requiring only the depression of the keys, may also be much more rapid of manipulation than the two-motion record- ing-adding machine which, after depressing the keys for each item, requires the secondary opera- tion of pulling a crank forward or operating a push bar that connects the motor. The recording-adding machine being designed to print the items and answers of addition, requires power for the printing which cannot be supplied by key depression. Thus an extra means for sup- plying that power must be provided in the form of a crank lever, or in the latest machines by a motor. The keys in such machines serve only as digital control to gauge the setting of mechanism which prints the items and adds them together. The secondary motion operates the mechanism to print and add and finally to clear the machine for the setting up of the next item. The recording of added columns of figures requires that the answer must always be printed. This demands special operation of devices provided for that purpose, which also adds to the time spent in the operation of such machines as compared with the key-driven calculator. To state which of these two types of machines is the more useful would cause a shower of com- ment, and has nothing to do with the object of this article. Suffice it to say that where a printed record of items added together with their answer is required for filing purposes, or to bring together loose items like those in your bank statement, the recording-adding machine serves; but when rapid Recording, the primary feature of adding ma- chines that print Origin of Modern Calculating Machines calculation in addition, multiplication, subtraction or division, or when combinations of these forms of calculation are required, the key-driven calcu- lator is the practical machine for such work. Although the key-driven calculator is generally not so well known, it is, as stated, the oldest of the modern accounting machines, and its usefulness places it in the accounting room, where it is oft- times found employed by the hundreds in figuring up the day's work of accounting. Validity and The purpose of this book is based wholly upon priority of showing the validity and priority of invention which constitute true contributions to the Art of these two types of modern accounting machines; to place the facts for once and all time before the public in such a way that they may judge for themselves to whom the honor is due and thus settle the controversy that exists. The quibbling of court contests over the termin- ology of claims of patents owned by the various inventors have been set aside and only the true contributions to the Art which pertain to the fundamental principles that have made the modern machines possible, are here dealt with. The dates of patents on inoperative or imprac- tical machines have from time to time been held up to the public as instances of priority of inven- tion; but when the validity of these patents, as furnishing any real contributions to the Art, is questioned, they are not found to hold the theme or principle that made the modern machines pos- sible, and as inventions, fade into obscurity. The Art of either the calculating machine or the adding-recording machine is not new; it is, as a matter of fact, very old. As before stated, the Art Types of Ajtcient and Modern Machines 11 of "accounting machine" dates back to the tenth century, but the first authentic evidence of a work- ing machine is extant in models made by Pascal in 1642 (see illustration). The Pascal ]\Iachine Referring to the illustration, Fig. 1, of Pascal's machine on the opposite page, it will be noted that there are a series of square openings in the top of the casing ; under these openings are drums, each numbered on its cylindrical surface. As the machine illustrated was made to figure English currency, the two right-hand wheels are numbered for pence and shillings, while the six wheels to the left are numbered from 1 to 9 and for pounds. The pounds register-drums, or numeral wheels, are each operated by a train of gearing connecting them with a ten-armed turnstile wheel which form the hub and spokes of what appears to be a series of wheels on the top of the casing. While the spokes and hub are movable, the rims of these wheels are stationary and are numbered from 1 to 9 and 0. The geared relation between the turnstile wheels and the numeral wheels is such that rotating a turnstile will give like rotation to its numeral wheel. Assuming that the numeral wheel of any one of the difi'erent orders registered through its sight opening and the turnstile of the same order was moved one spoke of a rotation, it would move the wheel so that the would disappear and the figure 1 would appear ; now if we should move the same turnstile three more spokes the numeral wheel Blaise Pascal Description uf Pascal's invention Paifcal machine 12 Origik of Modern Calculating Machines would move likewise three spaces and the 4 would appear. A stop in the form of a finger reaching over the spokes is provided to stop the turnstile at the right point so that the figures on the numeral wheels may register properly with the sight openings in the casing. Conslruclional '^^^ figures on the wheel rims fast to the casing Jeatures of the are arranged anti-clockwise to register with the space between the spokes, the registering with the first space, the 1 with the second space and so on around the wheel. Thus by use of the finger or a stylo inserted in a space opposite the number to be added, the operator may move the spoked wheel or turnstile clockwise until stopped by the stop finger. By repeated selection and operation for each figure to be added, the wheels will be revolved through their cycles of rotation caused by the accumulation. As the numeral wheels complete each rotation the will appear, so that a registration of the tens must be made. Pascal provided for the accumula- tion of the tens by automatically turning the wheel of next higher order one point through the action of the lower wheel. The novel means employed for this transfer of the tens consisted of a one-step ratchet device operated by a pin in the train of gearing connected with the lower numeral wheel, which, as the lower wheel passed from 9 to 0, forced the lever to which the ratchet pawl was attached in a direction to cause the gearing of the higher numeral wheel to be ratcheted forward far enough to add one to the higher numeral wheel. Types of Ancient and Modern Machines 13 The direct actuation of a numbered wheel through its various degrees of rotation and the secondary feature of effecting a one-step movement to the numbered wheel of higher order (which seems to have been originated by Pascal) is the founda- tion on which nearly all the calculating machines have since been constructed to calculate the com- binations of the Arabian numerals represented in Addition, Multiplication, Subtraction and Division. In Fig. 2 of the illustration of Pascal's machine, the machine has been reversed, and the bottom of the casing, which is hinged, throw^n back, show- ing the numeral wheels and gearing of the differ- ent orders and the transfer levers for the carry of the tens. The Art of the modern machines is far removed from the older Art by its greatly increased capacity for rapid calculation which is found emanating from the provision of keys as the means of manipulation. To the unsophisticated, such a simple thing as applying keys to the ancient type of calculating machines that have been made and used for cen- turies, would seem but a simple mechanical appli- cation that the ordinary mechanic could accom- plish. But it was too great a problem for the many- renowned inventors of the older Art to solve. Even though the use of depressable keys was com- mon to many machines, especially the piano, they knew that the organized make-up of their machines could scarcely stand, without error, the slow action received from the crank motion or other means employed as manipulating devices. To place it within the power of an operator to operate their machines at such a speed as would obtain in the sudden striking of a key would result in chaos. IiicrciUied cainu ily of nuHiern • ttlculalor 14 Origin of Modern Calculating Machines Patent office a There is no room for doubt that some of these repository qi garlv inventors had the wish or desire to produce ineffectual "^ , • , -, .1 efforts such a key-driven machine and may have attempted to produce one. But as they lacked the advantage of an institution like the Patent Office in which they could leave a record of their inoperative in- ventions, and in view of the fact that they were dependent on producing an operating machine for credit, there is no authentic proof that they made attempts in this line. No. 7,074. D. D. PARMELEE. Calculator. Patented Feb. 5, 1850. Piirmelee Patent Drawings The Early Key-Driven Art MLE COLONEL D'OCAGNE, Ingenieur des Fonts et Chaussees, Professeur a I'Ecole • des Fonts et Chaussees, Repetiteur a TEcole Folytechnique, in his "Le Calcul simplifie," a historical review of calculating devices and ma- chines, refers to the key-driven machine as having first made its appearance in the Schilt machine of 1851, but that the Art reached its truly practi- cal fonn in America. In the latter part of his statement the professor is correct, but as to the first appearance of the key-driven machine the U. S. Fatent Office records show that a patent was issued to D. D. Parmelee in 1850 for a key-driven adding machine (see illustration). The Parmelee Machine By referring to the illustration of the Parmelee ' ^^irst attempt h , -.1 'i-'"' aepressaolr machine reproduced from the drawings of the keys for adding patent, the reader will notice that the patentee deviated from the established principle of using numeral wheels. In place of numeral wheels a long ratchet-toothed bar has been supplied, the flat faces of which are numbered progressively from the top to the bottom. As shown in Fig. 2 of these drawings, a spring- pressed ratchet pawl marked k, engages the teeth of the ratchet or numeral bar. The pawl k, is piv- oted to a lever-constructed device marked E, the plan of which is shown in Fig. 3. This lever 17 was made in America 18 Origin of Modern Calculating Machines Description of Parmelee machine Foreign diyil adders device is pivoted and operated by the keys which are provided with arms d, so arranged that when any one of the keys is depressed the arm contacts with and operates the lever device and its pawl k to ratchet the numeral bar upwards. Another spring-pressed ratchet pawl marked m (see Fig. 2) is mounted on the bottom of the cas- ing and serves to hold the numeral bar from re- turning after a key-depression. It will be noted from Fig. 1 that the keys extend through the top of the casing in progressively varying heights. This variation is such as to allow the No. 1 key to ratchet up one tooth of the numeral bar, the No. 2 key two teeth, etc., pro- gressively. By this method a limited column of digits could be added up by depressing the keys corresponding to the digits and the answer could be read from the lowest tooth of the numeral bar that protruded through the top of the casing. It is evident that if the Parmelee machine was ever used to add with, the operator would have to use a pussyfoot key-stroke or the numeral bar would over-shoot and give an erroneous answer, as no provision was made to overcome the momen- tum that could be given the numeral bar in an adding action. The foreign machines of the key-driven type were made by V. Schilt, 1851 ; F. Arzberger, 1866 ; Stetner, 1882; Bagge, 1882; d'Azevedo, 1884; Petetin, 1885; Maq Meyer, 1886. These foreign machines, like that of Parmelee, according to M. le Colonel d'Ocagne, were limited to the capacity of adding a single column of digits at a time. ITiat is, either a column of units or tens or hundreds, etc., at a time. Such machines, of course, required The Early Key-Driven Art 19 the adding first of all the units, and a note made of ^. .... the total ; then the machine must be cleared and adders lack the tens figure of the total, and hundreds, if there '^'pacity be one, must then be added or carried over to the tens column the same as adding single columns mentally. On account of these machines having only a capacity for adding one order or column of digits, the unit value 9 was the greatest item that could be added at a time. Thus, if the overflow in adding the units column or any other column amounted to more than one place, it required a multiple of key- depressions to put it on the register. For example, suppose the sum of adding the units columns should be 982, it would require the depression of the 9-key ten times and then the 8-key to be struck, to put the 98 on the machine. This order of manipulation had to be repeated for each denom- inational column of figures. Another method that could be used in the man- ipulation of these single-order or digit-adding machines was to set down the sum of each order as added with its units figure arranged relative to the order it represents the sum of, and then men- tally add such sums (see example below) the same as you would set down the sums in multiplication and add them together. Example of method that may be used with single column adder. 982- 563 384 125 170012 20 Origin of Modern Calculating Machines Such machines, of course, never became popu- lar because of their hmited capacity, which re- quired manj^ extra movements and caused mental strain without offering an increase in speed of cal- culation as compared with expert mental calcula- tion. There were a number of patents issued in the United States on machines of this class which may well be named single digit-adders. Some early U.S. The machines of this type which were patented ^° ^^d\git adding ^^ the United States, preceding the first practical machines multiple order modern machine, were patented by D. D. Parmelee, 1850; W. Robjohn, 1872; D. Carroll, 1876; Borland & Hoffman, 1878; M. Bouchet, 1883; A. Stettner, 1883; Spalding, 1884; L. M. Swem, 1885 and 1886 ; P. T. Lindholm, 1886 ; and B. F. Smith, 1887. All of these machines varied in construction but not in principle. Some were really operative and others inoperative, but all lacked what may be termed useful capacity. To those not familiar with the technical fea- tures of the key-driven calculating machine Art, it would seem that if a machine could be made to add one column of digits, it would require no great invention or ingenuity to arrange such mechanisms in a plurality of orders. But the im- possibility of effecting such a combination with- out exercising a high degree of invention will become evident as the reader becomes familiar with the requirements, which are best illustrated through the errors made by those who tried to produce such a machine. As stated, the first authentic knowledge we have of an actual machine for adding is extant in models The Early Key-Driven Art 21 made by Pascal in 1642, which were all multiple- order machines, and the same in general as that shown in the illustration, page 10. History shows that Europe and other foreign countries have been using calculating machines for centuries. Like that of Pascal's, they were all multiple-order machines, and, although not key- driven, they were capable of adding a number of columns or items of six to eight places at once with- out the extra manipulation described as necessary with single-order digit adding machines. A num- ber of such machines were made in the United States prior to the first practical multiple-order key-driven calculator. This fact and the fact that the only operative key-driven machines made prior to 1887 were single-digit adders are significant proof that the backward step from such multiple-order machines to a single-order key-driven machine was from the lack of some unknown mechanical functions that would make a multiple-order key-driven cal- culator possible. There was a reason, and a good one, that kept the inventors of these single-order key-driven machines from turning their invention into a multiple-order key-driven machine. It is folly to think that all these inventors never had the thought or wish to produce such a machine. It is more reasonable to believe there was not one of them who did not have the wish and who did not give deep thought to the subject. There is every reason to believe that some of them tried it, but there is no doubt that if they did it was a failure, or there would be evidence of it in some form. Calculating ma- chines in use abroad fur centuries First key-driven machines no improvement to the Art 22 Origin of Modern Calculating Machines The Hill Machine The U. S. Patent Office records show that one ambitious inventor, Thomas Hill, in 1857 secured a patent on a multiple-order key-driven calculating machine (see illustration), which he claimed as a new and useful invention. The Hill patent, how- ever, was the only one of that class issued, until the first really operative modem machine was made thirty years later, and affords a fine example by which the features that were lacking in the make- up of a really operative machine of this type may be brought out. Descriptionofihr The illustrations of the Hill machine on the Hillmachw opposite page, reproduced from the drawings of the patent, show two numeral wheels, each having seven sets each of large and small figures running from 1 to 9 and the cipher marked on their pe- riphery. The large sets of figures are arranged for addition or positive calculation, and the small figures are arranged the reverse for subtraction or negative calculation. The wheels are provided with means for the carry of the tens, very similar to that found in the Pascal machine. Each of the two wheels shown are provided with ratchet teeth which correspond in number with the number of figures on the wheel. Spring-pressed, hook-shaped ratchet pawls marked b, are arranged to be in constant engage- ment with the numeral wheels. These pawls are each pivotally mounted in the end of the levers marked E, which are pivoted at the front end of the casing. The levers E, are held in normal or upward posi- tion by springs f, at the front of the machine. No. 18,692. T. HILL. ARITHMOMETER. Patented Nov. 24. 1857. Hill Patent Drawint 24 Origin of Modern Calculating Machines Above each of these levers E, are a series of keys which protrude through the casing with their lower ends resting on the levers. There are but six keys shown in the drawing, but the specification claims that a complete set of nine keys may be supplied for each lever. The arrangement and spacing of the keys are such that the greater the value of the key the nearer it is to the fulcrum or pivot of the lever E. The length of the key stem under the head or but- ton of each key is gauged to allow depression of the key, the lever E and pawl b, far enough to cause the numeral wheel to rotate as many numeral places as the value marking on the key. A back-stop pawl for the numeral wheels, marked p, is mounted on a cross-rod at the top of the machine. But one of these pawls are shown, the shaft and the pawl for the higher wheel being broken away to show the device for transferring the tens to the higher wheel. The transfer device for the carry of the tens is a lever arrangement constructed from a tube F, mounted on the cross-rod m, with arms G and H. Pivoted to the arm G, is a ratchet pawl i, and attached to the pawl is a spring that serves to hold the pawl in engagement with the ratchet of the higher-order numeral wheel, and at the same time, through its attachment with the pawl, holds the lever arms G and H retracted as shown in the drawing. As the lower-order numeral wheel passes any one of its points from 9 to 0, one of the teeth or cam lugs n, on the wheel will move the arm H, of the transfer lever forward, causing the pawl i, to move the higher-order wheel one step to register the accumulation of the tens. The Early Key-Driven Art 25 The functions of the Hill mechanism would, perhaps, be practical if it were not for the physical law that "bodies set in motion tend to remain in motion," Considerable unearned publicity has been given the Hill invention on account of the patent office model having been placed on exhibit in the National Museum at Washington. Judging from the out- ward appearance of this model, the aiTangement of the keys in columns would seem to impart the impression that here was the foundation of the modern key-driven machine. The columnar prin- ciple used in the arrangement of the keys, how- ever, is the only similarity. The Hill invention, moreover, was lacking in the essential feature necessary to the make-up of such a machine, a lack that for thirty years held the ancient Art against the inroads of the modern Art that finally displaced it. The feature lacking was a means for controlling the action of the mechan- ism under the tremendously increased speed pro- duced by the use of depressable keys as an actuat- ing means. Hill made no provision for overcoming the lightning-speed momentum that could be given the numeral wheels in his machine through manipu- lation of the keys, either from direct key-action or indirectly through the carry of the tens. Imagine the sudden whirl his numeral wheel would receive on a quick depression of a key and then consider that he provided no means for stopping these wheels; it is obvious that a correct result could not be obtained by the use of such mechanism. Some idea of what would take place in the Hill machine under manipulation by an operator may Hill machine at i\'alional Museum Inoperativeness of Hilt machine 26 Origin of Modern Calculating Machines be conceived from the speed attained in the oper- ation of the keys of the up-to-date modern key- driven machine. High speed uj Operators on key-driven machines oftentimes keydrm attain a speed of 550' key strokes a minute in multiplication. Let us presume that any one of these strokes may be a depression of a nine key. The depression and return, of course, represents a full stroke, but only half of the stroke would represent the time in which the wheel acts. Thus the numeral wheel would be turned nine of its ten points of rotation in an eleven hundredth (1/1100) of a minute. That means only one-ninth of the time given to half of the key stroke, or a ninety- nine hundredth (1/9900) of a minute; a one hun- dred and sixty-fifth (1/165) part of a second for a carry to be effected. Camera slow If you have ever watched a camera-shutter work carn'^o/thetnl ^^ ^ twenty-fifth of a second exposure, which is the average time for a snap-shot with an ordinary camera, it will be interesting to know that these controlling devices of a key-driven machine must act in one-fifth the time in which the shutter allows the daylight to pass through the lens of the camera. Think of it; a machine built with the idea of offering the possibility of such key manipulation and supplying nothing to overcome the tremendous momentum set up in the numeral wheels and their driving mechanism, unless perchance Hill thought the operator of his machine could, mentally, con- trol the wheels against over-rotation. Lack of a proper descriptive term used to refer to an object, machine, etc., oftentimes leads to the use of an erroneous term. To call the Hill inven- 2 Sheets-Sheen Q. W. CHAPIN. ADDIKO MACHINE. Patented Feb. 8, 1870. 2 Sheets-Sheets G. W. CHAPIN. ADDINQ MACHINE. No. 99,633. Patented Feb. 8, 1870. ^'rjf.3 Chapiii I'iiteiit Dni\ving.s The Early Key-Driven Art 29 tion an adding machine is erroneous since it would not add correctly. It is as great an error as it would be to refer to the Langley aeroplane as a flying machine. When the Wright brothers added the element that was lacking in the Langley plane, a real flying machine was produced. But without that element the Langley plane was not a flying machine. Like- wise, without means for controlling the numeral wheels, the Hill invention was not an adding machine. The only term that may be correctly applied to the Hill invention is "adding mechan- ism," which is broad enough to cover its incom- pleteness. And yet many thousands of people who have seen the Hill invention at the National Museum have probably carried away the idea that the Hill invention was a perfectly good key-driven adding machine. Lest we leave unmentioned two machines that might be misconstrued to hold some of the fea- tures of the Art, attention is called to patents issued to G. W. Chapin in 1870 (see illustration on opposite page), and A. Stark in 1884 (see illustra- tion on page 32). Chapin Machine Referring to the illustration reproducing the drawings of the Chapin patent, the reader will note that in Fig. 1 there are four wheels marked V. These wheels, although showing no numerals, are, according to the specification, the numeral wheels of the machine. The wheels are provided with a one-step ratchet device for transferring the tens, consisting of the spring frame and pawl shown in Fig. 3, which is operated by a pin in the lower wheel. ///■// machine merely adding mechanism, in- complete as operative inachilir Chapin and Stark patents Description of Chapin machine 30 Origin of Modern Calculating Machines In Fig. 1 the units and tens wheel are shown meshed with their driving gears. These gears are not numbered but are said to be fast to the shafts N and M, respectively (see Fig. 2). Fast on the shaft M, is a series of nine ratchet- toothed gears marked O, and a like series of gears P, are fast to the shaft N. Co-acting with each of these ratchet-toothed gears is a ratchet-toothed rack F, pivoted at its lower end to a key lever H, and pressed forward into engagement with its ratchet gear by a spring G. The key levers H, of which there are two sets, one set with the finger-pieces K and the other with the finger-pieces J, are all pivoted on the block I, and held depressed at the rear by an elastic band L. The two sets of racks F, are each provided with a number of teeth arranged progressively from one to nine, the rack connected with the No. 1 key having one ratchet tooth, the No. 2 having two teeth, etc. inoperaiweness By this arrangement Chapin expected to add machine the units and tens of a column of numerical items, and then by shifting the numeral wheels and their transfer devices, which are mounted on a frame, designed for that purpose, he expected to add up the hundred and thousands of the same column of items. It is hardly conceivable that the inventor should have overlooked the necessity of gauging the throw of the racks F, but such is the fact, as no provision is made in the drawings, neither was mention made of such means in the specification. Even a single tooth on his rack F, could, under a quick key-stroke, overthrow the numeral wheels, and the same is true of the carry transfer mechanism. n g* m ■< a f\ W |i From the Stark Patent Drawings maimmmammmmim 1 The Early Key-Driven Art The Chapin machine, Hke that of Hill, was made without thought as to what would happen when a key was depressed with a quick stroke, as there was no provision for control of the numeral wheels against overthrow. As stated, the machine was designed to add two columns of digits at a time, and with an attempt to provide means to shift the accumulator mechanism, or the numeral wheels and carry-transfer devices, so that columns of items having four places could be added by such a shift. Such a machine, of course, offered less than could be found in the Hill machine, and that was nothing at all so far as a possible operative machine is concerned. The Stark Machine The reproduction of the patent drawings of the Stark machine illustrated on the opposite page show a series of numeral wheels, each provided with three sets of figures running from 1 to 9 and 0. Pivotally mounted upon the axis of the numeral Description of wheels at each end are sector gears E^ and arms E*, '*^'°'',^. ^ ° ' machine in which are pivoted a square shaft E, extended from one arm to the other across the face of the numeral wheels. The shaft E, is claimed to be held in its normal position by a spring so that a pawl, E-, shif tably mounted on the shaft, designed to ratchet or actuate the numeral wheels forward, may en- gage with any one of the numeral wheel ratchets. A bail marked D, is pivoted to standards AS of the frame of the machine, and is provided with the two radial racks D', which mesh with the sec- tor gears E\ It may be conceived that the act of depressing the bail D, will cause the actuating 34 Origin of Modern Calculating Machines pawl E-, to operate whichever numeral wheel it engages the ratchet of. The bail D, is held in its normal position by a spring D-, and is provided with nine keys or fin- ger pieces d, eight of which co-act with the stepped plate G, to regulate the additive degree of rotation given to the numeral wheels, while the ninth has a fixed relation with the bail and the bail itself is stopped. The keys d, marked from 1 to 8, are pivoted to the bail in such a manner that their normal rela- tion to the bail will allow them to pass by the steps on the stepped plate G, when the bail is depressed by the fixed No. 9 key. When, however, any one of the keys numbered from 1 to 8 is de- pressed, the lower end of the shank of the key will tilt rearward, and, as the bail is depressed, offers a stop against the respective step of the plate G, arranged in its path, thus stopping further action of the actuating pawl E^, but offering nothing to prevent the continuation of the force of momen- tum set up in the numeral wheels by the key action. There was small use in stopping the action of the pawl E^, if the ratchet and numeral wheel, im- pelled by the pawl, could continue onward under its momentum. The carry of the tens transfer device is of the same order as that described in the Pascal and Hill machines; that is, a one-step ratchet-motion actuated by a cam lug or pin from the lower wheel. The carry transfer device consists of the lever F, and pawl f*, acting on the ratchet of the upper wheel which is operated by the cam lugs b% of the lower wheel acting on the arms f^ and f ^ of the lever F. W. ROBJOHN improvement in Calculating Machines. No, 130,244. 2 Slieels--Sheel 1. Patented Aug. 6, 1872. ® ♦x^./ .9 ® ® ® ® ®^® ® ® ® eJTjr X From the Kobjolin Patent Drawings The Early^"Key-Driven Art 37 The machine shown in the Stark patent was provided with but one set of keys, but the arrange- ment for shifting the driving ratchet pawl E-, from one order to another, so that the action of the keys may rotate any one of the numeral wheels, gave the machine greater capacity than the single digit adders ; but as with the Chapin machine, of what use was the increase in capacity if the machine would not add correctly. That is about all that may be said of the Stark machine, for since there was no means provided by which the rotation of numeral wheels could be controlled, it was merely a device for rotating numeral wheels and was therefore lacking in the features that would give it a right to the title of an adding machine. The nine-key scheme of the Stark invention, connectable to the different orders, was old, and was first disclosed in the U. S. Patent to O. L. Castle in 1857 (a machine operated by a clock- spring wound by hand), but its use in either of these machines should not be construed as holding anything in common with that found in some of the modern recording adders. The Castle machine has not been illustrated because it does not enter into the evolution of the modem machine. The ancient Art, or the Art prior to the inven- tion of Parmelee, consisted of mechanism which could be controlled by friction devices, or Geneva gear-lock devices, that were suitable to the slow- acting type of manipulative means. The first attempt at a positive control for a key- driven adding device is found in a patent issued to W. Robjohn in 1872 (see illustration). As will be noted, this machine was referred to in the fore- Inoperativencss of Slark machine .\ine keys com- mon to a plural- ity of orders 38 Origin of Modern Calculating Machines going discussion as merely a single-digit adding machine, having the capacity for adding but one colum.n of digits at a time. RoBJOHN Machine Referring to the illustration of the patent draw- ings of the Robjohn machine, it will be noted that there are three sight openings in the casing through which the registration of the numeral wheels may be read. The numeral wheels, like those of all machines of this character, are connected by devices of a similar nature to those in the Hill machine for carrying the tens, one operating between the units and tens wheel and another be- tween the tens and hundredths wheel. Description The units wheel shown in Fig. 3 is connected by ^'^ macMne ^^^^^^^ ^^ a long pin-wheel rotor, marked E, so that any rotation of the rotor E, will give a like rotation to the units numeral wheel to which it is entrained by gearing. To each of the nine digital keys, marked B, is attached an engaging and disengaging sector gear device, which, as shown in Fig. 3, although nor- mally not in engagement with the rotor E, will upon depression of its attached key, engage the rotor and turn it. A stop device is supplied for the key action, which in turn was supposed to stop the gear action; that seems rather doubtful. However, an alternative device is shown in Figs. 4 and 5, which provides what may without question be called a stop device to prevent over-rotation of the units wheel under direct key action. It will be noted that the engaging and disengag- ing gear device is here shown in the form of a (No Model.) No. 314.561, M. BOUCHET. 2 Sheets-Sheet 1. ADDING MACHINE. Patented Mar. 31, 1885. WITNESS^. INVENTOR. From Drawings of Bouchet Patent 314,501 The Eakly Key-Driven Art 41 gear-toothed rack and that the key stem is pro- vided with a projecting arm ending in a down- wardly projecting tooth or detent which may engage the rotor E, and stop it at the end of the downward key action. While the stopping of the rotor shows a control in the Rob John machine which takes place under direct action from the keys to prevent overthrow of the units numeral wheel, it did not prevent the overflow of the higher or tens wheels, if a carry should take place. There was no provision for a control of the numeral wheels under the action received from the carry of the tens by the transfer mechanism. The first attempt to control the carried wheel First control for a in a key-driven machine is found in a patent issued ^"^^^f"^ numeral to Bouchet in 1882 (see illustration on opposite page) ; but it was a Geneva motion gearing which, as is generally known, may act to transmit power and then act to lock the wheel to which the power has been transmitted until it is again to be turned through the same source. Such a geared up and locked relation between the numeral wheels, of course, made the turning of the higher wheel (which had been so locked) by another set of key- mechanism an impossibility. Bouchet ^Machine The illustration of the Bouchet machine on the opposite page was reproduced from the drawings of the patent which is the nearest to the machine that was placed on the market. The numeral wheels, like most of the single-digit adders, are three in number, and consist of the prime actuated, or units wheel, and two overflow wheels to receive machine 42 Origin of Modern Calculating Machines the carry of the tens. The units wheel has fixed to it a long 10-tooth pinion or rotor I, with which nine internal segmental gear racks L, are arranged to engage and turn the units wheel through their nine varying additive degrees of rotation. Description "^^^ segmental gear racks L, are normally out of of Bouchet mesh with the pinion I, and are fast to the key levers E, in such a manner that the first depres- sion of a key causes its rack to rock forward and engage with the pinion I, and further depression moves the rack upward and rotates the pinion and units numeral wheel. It will be noted that this en- gaging and disengaging gear action is in principle like that of Robjohn. The transfer devices for the carry of the tens, as already stated, belong to that class of mechan- ism commonly knov/n as the "Geneva motion." It consists of a mutilated or one-tooth gear fast to the units wheel operating with a nine-tooth gear, marked DS loosely mounted on an axis parallel to the numeral wheel axis. Each revolution of the units wheel moves the nine-tooth gear three spaces, and in turn moves the next higher numeral wheel to which it is geared far enough to register one point or the carry. A circular notched disc, marked S, is fast to the units wheel, and the nine-tooth gear D^ has part of two out of every three of its teeth mutilated or cut away to make a convex sur- face for the notched disc to rotate in. With such construction the nine-tooth gear may not rotate or become displaced as long as the periphery of the disc continues to occupy any one of the three convex spaces of the nine-tooth gear. When, however, the notch of the disc is presented to the mutilated portion of the nine-tooth gear, The Early Key-Driven Art 48 the said gear is unlocked. This unlocking is co- incident to the engagement of the single tooth of the numeral wheel-gear with the nine-tooth gear and the passing of the numeral wheel from 9 to 0, during which the nine-tooth gear will be moved three spaces, and will be again locked as the notch in the disc passes and the periphery fills the. next convex space of the mutilated nine-tooth gear. The Bouchet machine was manufactured and sold to some extent, but never became popular, as it lacked capacity. Machines of such limited capacity could not compete with ordinary ac- countants, much less with those who could mentally add from two to four columns at a clip. Aside from the capacity feature, there was another reason why these single-order machines were useless, except to those who could not add mentally. Mul- tiple forms of calculation, that is, multiplication and division, call for a machine having a multi- plicity of orders. The capacity of a single order would be but 9x9, which requires no machine at all — a seven-year-old child knows that. To multi- ply 58964x6824, however, is a different thing, and requires a multiple-order calculator. It is perhaps well at this time to point out the misuse of the term calculating where it is applied to machines having only a capacity for certain forms of calculating as compared with machines which perfoiTn in a practical way all forms of cal- culation, that is, addition, multiplication, subtrac- tion and division. To apply the term "calculating machine" to a machine having anything less than a capacity for all these forms is erroneous. An adding machine may perform one of the forms of calculation, but to call it a calculating Bouchel machine marketed Misuse of the term^Calculatirvj Machine" 44 Origin of Modern Calculating Machines machine when it has no capacity for division, sub- traction or multiplication, is an error ; and yet we find the U. S. Patent Office records stuffed full of patents granted on machines thus erroneously named. The term calculating is the broad term covering all forms of calculation, and machines performing less should be designated according to their specific capacities. It is true that adding is calculating, and under these circumstances, why then may not an adding machine be called a calculator? The answer is that it may be calculating to add ; it may be calcu- lating to either subtract, multiply or divide; but if a machine adds and is lacking in the means of performing the other forms of calculation, it is only part of a calculating machine and lacks the features that will give it title to being a full-fledged calculator.* Considerable contention was raised by parties in a late patent suit as to what constituted the make-up of a calculating machine. One of the attorneys contended that construction was the only thing that would distinguish a calculating machine. But as machines are named by their functioning, the contention does not hold water. That is to say: A machine may be a calculating machine and yet its construction be such that it performs its functions of negative and positive calculation without reversal of its action. Again, a machine may be a calculating machine and operate in one direction for positive calcula- tion and the reverse for negative calculation. As long as the machine has been so arranged that all forms of calculation may be performed by it with- * Note: The title of this book does not coincide with the above argument, but in view of the common use of the term "calculating" its application is better understood. ii5«»M IW «wwww»w- /'/^ // ^^ j-if- mmmm-i Drawings of Spalding Patent No. 29.3,809 The Early Key-Driven Art 47 Spalding machine out mental computation, and the machine has a reasonable capacity of at least eight orders, it should be entitled to be called a calculating machine. The Spalding Machine The next machine that has any bearing on the key-driven Art of which there is a record, is illus- trated in a patent granted to C. G. Spalding in 1884 (see illustration on opposite page). The Spalding invention, like that of Bouchet, was pro- vided with control for its primary actuation and control for its secondary or carrying actuation. Referring to the Spalding machine reproduced Description of from the drawings of his patent, the reader will note that in place of the units and tens numeral wheels, a clock hand has been supplied, co-operat- ing with a dial graduated from to 99, showing the figures 5, 10, 15, etc., to 95, for every five graduations. Another similar hand or arrow and dial to reg- ister the hundreds is also provided, having a capac- ity to register nineteen hundred. Attached to the arrows, through a shaft connection at the back of the casing are ratchet wheels, having respectively the same number of teeth as the graduation of the dial to which each hand belongs. Co-operating with the hundred-tooth ratchet of the units and tens register hand is a ratchet and lever motion device (see Fig. 2) to turn the arrow from one to nine points of the graduation of the dial. The ratchet and lever-motion device consists of the spring-pressed pawl E, mounted on the lever arm D, engaging the hundred-tooth ratchet, the link or push-rod F, the lever G, and its spring 0. It will be noted that a downward action of the lever G, will, through the rod F, cause a like down- 48 Origin of Modern Calculating Machines ward action of the lever D, causing the ratchet pawl E to be drawn over the ratchet teeth. Upon the release of the lever G, the spring 0, will return it to its normal position and through the named connecting parts, ratchet forward the arrow. The normal position of the pawl E is jammed into the tooth of the ratchet and against the bracket C, that forms the pivot support for the pivot shaft of the arrow. This jammed or locked combination serves to stop the momentum of the ratchet wheel at the end of the ratcheting action, and holds the wheel and its arrow normally locked until the lever G is again depressed. The means for gauging the depression and additive degrees of action of the lever G is pro- duced through the slides or keys marked a, hav- ing finger-pieces c, springs f, and pins e, bearing against the top of the lever G, combined with what may be called a compensating lever marked K. The specification of the patent states that the depression of a key will depress the lever G and the free end will engage the bent end t, of the compensating lever K, and rock its envolute curved arm M, upward until it engages the pin e of the key, which will block further motion of the parts. The effectiveness of the construction shown for the lever K is open to question. The carry of the hundreds is accomplished by means of a one-step ratchet device represented by the parts lever R, pawl T, spring P, and operating pin g. When the hundred-tooth ratchet nears the end of its revolution, the pin g, made fast therein, engages the free end of the ratchet lever R, and depresses it ; and as the hand attached to the hun- dred-tooth ratchet wheel passes from 99 to the The Early Key-Driven Art pin g passes off the end of the ratchet lever R, and the spring P retracts the lever ratcheting the twenty-tooth wheel and its arrow forward one point so that the arrow registers one point greater on the hundreds dial. Although the Spalding means of control under carrying differed from that of Bouchet in con- struction, its function was virtually the same in that it locked the carried or higher wheel in such a manner as to prevent the wheel from being oper- ated by an ordinal set of key mechanism. And the control under key action would prevent a carry being delivered to that order through the locked relation of the ratchet and pawl E. Prime aclualion of a carried wheel imf>ossihle in the Spalding ma- chine Wi The Key-Driven Calculator 'HILE these single digit adding machines have been used to illustrate how the con- trol, which was lacking in the Hill inven- tion, had been recognized by other inventors as a necessary requisite to the key-drive, it should not be construed that such carrying control as had been applied to their inventions was of a type that could be used in the Hill machine or in any mul- tiple-order key-driven machine. It was thirty years after the first attempt to control a key- driven machine was made before an operative multiple-order key-driven machine, with a con- trol that would prevent over-rotation, was finally invented. Theory versus Theoretically, it would seem that the only fea- ihe concrete ^^j.g ^^ element lacking in the Art prior to 1886, to produce a real key-driven calculator was means that would control the carrying and also leave the carried wheel free for key actuation. It was, how- ever, quite a different problem. Theoretical func- tions may be patched together to make a theo- retical machine; but that is only theory and not the concrete. To take fragmental parts of such machines as were disclosed in the Art and patch them together into anything practical was impossible, even if one had been familiar with the Art and could devise mechanism to supply the new element. That is, leaving aside the broad or generic theoretical 50 The Key-Driven Calculator 51 elements, which today, from knowledge gained by later inventions, serve the make-up of a key-driven calculator, there was still lacking any concrete example or specific design of a whole machine, as there was no such machine disclosed in the draw- ings of patents, or any known mechanism which, if arranged in multiples, would be operative as a practical machine even if mechanism to supply the new element were to be added. In other words, while it is conceded from our present knowledge that all but one of the generic theoretical elements had been solved as disclosed in the various before-named machines, it required the application of these elements in a different way from anything before disclosed; which in itself required a different concrete form of the generic principles for the whole machine as well as a generic form of invention covering the new theoretical element. It may be easy to analyze that which exists, but quite a different story to conceive that which did not exist. With reference to the Art, however, the production of the new element is a feature that may be credited without question. The con- crete does not enter into it other than as proof that a new feature has been created. While the discussion of the Art from a scientific standpoint brings together in after years what has been accomplished by different inventors, it is doubt- ful whether any of these early inventors had other knowledge than what may possibly have been ob- tained from seeing one of the foreign-made crank- driven machines. All inventors work with an idea obtained from some source, but on the whole few copy inventions of others. When an Art is fully established, however, and machines representing . \ // but one uf I he generic ele- ments solved Orujinalily of inventions 52 Origin of Modern Calculating Machines the Art are to be found on the market and the principal features of such machines are portrayed in a later patent, it may rightly be called a copy. To assume, however, that a novice has taken the trouble to delve into the archives of the patent office and study the scattered theoretical elements of the Art and supply a new element to make a combination that is needed to produce a practical key-driven calculator, is not a probable assump- tion. But allowing such assumption were possible, it is evident that from anything that the Art disclosed prior to 1887 it was not possible to solve the concrete production of a key-driven calculator. A conception In 1884, a young machinist, while running a ^ jinaUolation Planer, conceived an idea from vv^atching its ratchet feed motion, which was indirectly responsible for the final solution of the multiple-order key-driven calculating machine. The motion, which was like that to be found on all planing machines, could be adjusted to ratchet one, two, three, four or more teeth for a fine or coarse feed. While there is nothing in such a motion that would in any way solve the problem of the mod- em calculator, it was enough to excite the ambi- tions of the man who did finally solve it. It is stated that the young man, after months of thought, made a wooden model, which he finished early in 1885. This model is extant, and is illus- trated on the opposite page. The inventor was Dorr E. Felt, who is well known in the calculating-machine Art as the man- ufacturer of the "Comptometer," and in public life as a keen student of economic and scientific subjects. The wooden model, as will be noted, was crude, but it held the nucleus of the machine to come. -Macaroni I'.n.x" Ahuit-l \ The Key-Driven Calculator 55 Mr. Felt has given some interesting facts re- garding his experience in making the wooden model. He says: "Watching the planer-feed set me to KvoluUon oj an scheming on ideas for a machine to simplify the inveniion hard grind of the bookkeeper in his day's calcula- tion of accounts. "I realized that for a machine to hold any value to an accountant, it must have greater capacity than the average expert accountant. Now I knew that many accountants could mentally add four columns of figures at a time, so I decided that I must beat that in designing my machine. There- fore, I worked on the principle of duplicate denom- inational orders that could be stretched to any ca- pacity within reason. The plan I finally settled on is displayed in what is generally known as the "Macaroni Box" model. This crude model was made under rather adverse circumstances. "The construction of such a complicated machine from metal, as I had schemed up, was not within my reach from a monetaiy standpoint, so I decided to put my ideas into wood. "It was near Thanksgiving Day of 1884, and I Trials of an decided to use the holiday in the construction of the wooden model. I went to the grocer's and selected a box which seemed to me to be about the right size for the casing. It was a macaroni box, so I have always called it the macaroni box model. For keys I procured some meat skewers from the butcher around the corner and some staples from a hardware store for the key guides and an assort- ment of elastic bands to be used for springs. When Thanksgiving day came I got up early and went to work with a few tools, principally a jack knife. ini'prilor Dorr E. Fi-lt 56 Origin of Modern Calculating Machines "I soon discovered that there were some parts which would require better tools than I had at hand for the purpose, and when night came I found that the model I had expected to construct in a day was a long way from being complete or in working order. I finally had some of the parts made out of metal, and finished the model soon after New Year's day, 1885." Tliejirsl By further experimenting the scheme of the Comptometer ^ooden modcl was improved upon, and Felt pro- duced, in the fall of 1886, a finished practical machine made of metal. This machine is illus- trated on the opposite page. The Felt Calculating Machine Referring to the illustration of Felt's first metal machine, it will be noted that the machine has been partly dismantled. The model was robbed of some of its parts to be used as samples for the manufacture of a lot of machines that were made later. In view of the fact that this machine is the first operative multiple-order key-driven calculat- ing machine made, it seems a shame that it had to be so dismantled; but the remaining orders are operative and serve well to demonstrate the claims held for it. Felt patent The mechanism of the machine is illustrated in the reproduction of the drawings of Felt's patent, 371,496, on page 58. The specification of this patent shows that it was applied for in March, 1887, and issued October 11, 1887. From the outward appearance of the machine it has the same general scheme of formation as is disclosed in the wooden model. The constructional scheme of the mechanism consists of a series of numeral wheels, marked A 371,^96 (5)®@®©@0®@ 0C.® @ ® © @ © @ © ® ® ® @ ® © From Drawings of Felt Patent No. .371,490 The Key-Driven Calculator in the patent drawings. Each wheel is provided Description of . , , 11 1 J.- -ii- ^u f^^'^ calculator With a ratchet wheel, and co-acting with the ratchet is a pawl mounted on a disc E-, carried by the pinion E\ which is rotatably mounted on the same axis as the numeral wheel. The arrangement of these parts is such that a rotating motion given any of the pinions E\ in a clockwise direc- tion, as shown in the drawings, would give a like action to their respective numeral wheels ; but any motion of the pinions in an anti-clockwise direc- tion would have no effect on the numeral wheels, owing to back-stop pawls K, and stop-pins T, pro- vided to allow movement of the numeral wheels in but one direction. Co-acting with each pinion E% is shown a long lever D, pivoted at the rear of the machine and provided with a segmental gear rack which meshes with the teeth of the pinion E\ This lever comes under what is now generally termed a segment lever. Each lever is provided with a spring S, which nonnally holds the front or rack end upward in the position shown in Fig. 1, and has co-acting with it a series of nine depressable keys which protrude through the casing and contact with the upper edge of the lever. The arrangement of the keys with their segment levers provides that the depression of any key will depress the segment lever of that order, which in turn will rotate the pinion E^ and its numeral wheel. While this arrangement is such that each key of a series gives a different degree of leverage action to the segment lever, and in turn a degree of rotation to the numeral wheel of the same order in accordance with the numerical value of the key Oeigin of Modern Calculating Machines depressed, it may be conceived that the ny)mentum set up by the quick stroke of a key would set the numeral wheel spinning perhaps two or three revo- lutions, or at any rate way beyond the point it should stop at to register correctly. To preserve correct actuation of the mechanism and overcome its momentum, Felt provided a detent toothed lever for each numeral wheel, which will be found marked J^ in the drawings. To this lever he linked another lever G, which extended below the keys, and arranged the length of the key stems so that when each key had revolved the numeral wheel the proper distance, the key will have engaged the lever G, and through the link connection will have caused the detent tooth of the lever J^ to engage one of the pins T, of the numeral wheel, thus bringing the numeral wheel and the whole train of mechanism to a dead stop. This combination was timed so that the (1) key would add one, the (2) key would add two, etc., up to nine for the (9) key. Thus the prime actuation of each wheel was made safe and positive. Recapitulation of Before explaining the means by which the carry *" ^'^^calculater ^f the tens was effected in the Felt machine without interfering with multiple - order prime actuation, it will perhaps help the reader to recap- itulate on what the x\rt already offered. Going back to the Art, prior to Felt's invention, there are a few facts worth reconsidering that point to the broadly new contributions presented in the Felt invention, and combining these facts with a little theory may perhaps give a clearer under- standing of what was put into practice. In most lines of mechanical engineering in the past, the term "theory" connected with mechanical The Key-Driven Calculator 61 construction was a bugaboo. But the solution of the modern calculating machine was wholly depen- dent upon it. Let us summarize on the Art, prior to Felt's in- vention. A calculating machine that would calcu- late, if we eliminate the key-driven feature, was old. The key-driven feature applied to adding mechanism was old as adapted to a single-order machine with a capacity for adding only a single column of digits. Hill attempted to make a multiple order key- driven machine, but failed because he did not theorize on the necessities involved in the physical laws of mechanics. Hill saw only the columnar arrangement of the ordinal division of the keyboard, and his thought did not pass beyond such relation of the keys for conveyance. There is no desire to belittle this feature, but it did not solve the problem that was set forth in the specification and claims of his patent ; neither did it solve it for anyone else who wished to undertake the making of such a machine. The introduction of keys as a driving feature in the calculating machine Art demanded design and construction suitable to control the new idiosyncrasies of force and motion injected into the Art by their use, of which the elements of in- ertia and momentum were the most troublesome. Hill, in the design and construction of his machine, ignored these two elementary features of mechanics and paid the penalty by defeat. The tremendous speed transmitted to the parts of a key-driven machine, which has already been illus- trated, required that lightness in construction which is absolutely necessary to reduce inertia to Why Hill failed to produce an operative ma- chine Idiosyncrasies of force and motion increased by use of keys Origin of Modern Calculating Machines Light construc- tion a feature Operative fea- tures necessary a minimum, should be observed. The Hill machine design is absolutely lacking in such thought. The dfameter of the numeral wheel and its heavy con- struction alone show this. Lightness of construc- tion also enters into the control of momentum when the mechanism must suddenly be brought to a dead stop in its lightning-speed action. A heavily- constructed numeral wheel like that shown in the Hill patent would be as hard to check as it would to start, even if Hill had provided means for check- ing it. Strength of design and construction, without the usual increase in weight to attain such end, but above all, the absolute control of momentum, were features that had to be worked out. Rob John partly recognized these features, but he limited the application of such reasoning to the prime actuation of a single order, and made nothing operable in a multiple key-driven machine. Spalding and Bouchet recognized that the appli- cation of control was necessary for both prime actuation and carrying, but, like Rob John, they devised nothing that would operate with a series of keys beyond a single order. An operative principle for control under prime actuation was perhaps present in some of the single-order key-driven machines, but whatever existed was applied to machines with keys arranged in the bank form of construction, and, to be used with the keys in columnar formation, required at least a new constructive type of inven- tion. But none of the means of control for carry- ing, prior to Felt's invention, held any feature that would solve the problem in a multiple-order machine. The Key-Driven Calculator While all the machines referred to have not been illustrated and described here, fair samples of the type that have any pertinence to the Art have been discussed, and those not illustrated would add nothing more than has been shown. A classifica- tion of the inventions referred to may be made as follows : Parmelee and Stetner had no carrying mechan- ism; Hill, Robjohn, Borland and Hoffman, Swem, Lindholm and Smith had no control for the carry. Carroll, Bouchet and Spalding show a control for the carrying action, which in itself would defeat the use of a higher wheel for prime actuation, and which obviously would also defeat its use in a multiple-order key-driven machine. One of the principal reasons why theory was necessary to solve the problem of the key-driven calculator existed in the impossibility of seeing what took place in the action of the mechanism under the lightning speed which it receives in operation. Almost any old device could be made to operate if moved slow enough to see and study its action; but the same mechanism that would operate under slow action would not operate cor- rectly under the lightning-speed action they could receive from key depression. Only theoretical reasoning could be used to analyze the cause when key-driven mechanism failed to operate correctly. Referring again to the drawings of the Felt patent, which illustrate the first embodiment of a multiple-order key-driven calculating machine, we find, what Felt calls in the claims and specifica- tions, a carrying mechanism for a multiple-order key-driven calculating machine. This mechanism was, as set forth in the specification, a mechanism Class ijicat ion of the features con- la iued in the early Art of key - (Irivrn nidcliines Carrying mech- an ism of Fell's calculator 64 Origin of Modern Caculating Machines Transfer devices Carrying mechan- ism versus mere transfer devices for transferring the tens, which have been accu- mulated by one order, to a higher order, by adding one to the wheel of higher order for each accumu- lation of ten by the lower order wheel. This, in the Felt machine, as in most machines, was eifected by the rotation of a numbered drum, called the numeral wheel, marked with the nine digits and cipher. The term "transfer device" for such mechanism was in common use, and as a term it fits certain parts of all classes of devices used for that pur- pose, whether for a crank-driven, key-driven, or any other type of multiple-order or single-order machine. But in the Felt invention we find it was not the simple device generally used for trans- ferring the tens. It was, in fact, a combination of devices co-acting with each other which, in the specification of the patent, was termed the carry- ing mechanism. Now, carrying mechanism may in a sense be termed a transfer device, as one of its functions is that of transferring power to carry the tens, but a mere transfer device may not be truthfully termed a carrying mechanism for a multiple-order key-driven machine unless it performs the func- tions that go to make up a correct carrying of the tens in that class of machine, and which we find laid down under the head of carrying mechanism in the Felt patents, where we find the first opera- tive carrying mechanism ever invented for a multiple-order key-driven machine. The functions demanded of such a piece of mechanism are as follows: First, the storing of power to perform the carry ; second, the unlock- ing of the numeral wheel to be carried ; third, the I The Key-Driven Calculator 65 delivery of the power stored to perform such carry; fourth, the stopping and locking of the carried wheel when it has been moved to register such carry; and fifth, clearing the carrying-lock during prime actuation. A seemingly simple oper- ation, but let those who have tried to construct such mechanism judge; they at least have some idea of it and they will no doubt bow their heads in acknowledgment of the difficulties involved in this accomplishment. Mechanism for carrying the tens in single digit adders was one thing, and such as was used could well be called a transfer device; but mechanism for carrying the tens in a real key-driven calculat- ing machine was another thing, and a feature not solved until Felt solved it, and justly called such combination of devices a "carrying mechanism." In the Felt machine, the carrying mechanism Details of Felt consisted of a lever and ratchet pawl action, con- mechanism structed of the parts M, m-, operated by a spring m, the pawl acting upon the numeral wheel pins T, to ratchet the wheel forward under the spring power. The power in the spring was developed from the rotation of the lower wheel, which through the means of an envolute cam* attached to left side of each wheel, operated the cariying lever in the opposite direction to that in which it was operated by the spring. As the carrying lever passed the highest point of the cam spiral and dropped off, the stored power in the spring re- tracted the lever M, and the pawl m-, acting on the higher order wheel pins T, and moved it one-tenth of a revolution. *Note: As all the drawings of the Felt patent are not reproduced here, the cam is not shown. 66 Origin of Modern Calculating Machines This part of the mechanism was in principle an old and commonly-used device for a one-step ratchet motion used in the carry of the tens. It served as a means of storing and transferring power from the lower wheel to actuate the higher wheel in a carrying operation, but a wholly un- qualified action without control. In the Felt machine a spring-actuated lever N, mounted on the same axis with the carrying lever, and provided with a detent stop-hook at its upper end, served to engage the numeral wheel at the end of its carried action, and normally hold it locked. An arm or pin P, fixed in and extending from the left side of the carrying lever and through a hole in the detent lever, acted to withdraw the detent lever from its locking engagement with the numeral wheel as the carrying lever reached the extreme point of retraction ; thus the wheel to be carried was unlocked. Pivoted to the side of the detent lever is a catch O. This catch or latch is so arranged as to hook on to a cross-rod q, especially constructed to co- act with the catch and hold the detent-lever against immediate relocking of the numeral wheel as the carrying lever and pawl act in a carrying motion. The latch has a tail or arm p, which co- acts with the pin P on the carrying lever in such a way as to release the latch as the carrying lever finishes its carrying function. Thus the detent lever N is again free to engage one of the control or stop-pins T to stop and lock the carried numeral wheel when the carrying lever and pawl, through the action of the spring stored in the carrying, has moved the wheel the proper distance. 1^ in ^ >-": H \. ^.. 9 1— ( en CO V. 1 P< ■-^ /-\^ \-v o H a W to < \ - N f ■ ^ - U- o o \ N ^\i m . »-H ■ ■ O < < DC .. ■ XT). UJ CM \ ■ »»_->, ^ O o Pi X o h ^ - g'^ G'' :^'' f\- Hili I'di- First Maiiul'acturin^- Tools of the "Coini)toinc't('r" i The Key-Driven Calculator 69 A lot of functions to take place in 1/165 of a second, but it worked. The timing of the stop and locking detents, of course, was one of the finest features. The normal engagem.ent of the carrying detent, it may be understood, would prevent the move- ment of the wheel by key action or prime actua- tion, but the patent shows how Felt overcame this. The carrying stop and locking detent lever N is provided with a cam-arm or pin N, which was ar- ranged to co-act with the cam disc E (see Fig. 1), fast to the prime actuating pinion E. The cam sur- face was short and performed its function during a short lost motion arranged to take place before the ratchet pawl would pick up and move the numeral wheel under key actuation. The camming action was outward and away from the center, and thus released the carrying stop from its locking position with the numeral wheel, and continued rotation of the pinion and cam disc would hold the lock out of action until the parts had returned to normal. With the return action of the keys, segment lever, pinion and cam disc, through the action of a spring attached to the segment lever, the carry- ing stop detent will again engage and lock the numeral wheel. Felt really started to manufacture his calculat- ing machine in the fall of 1886, after perfecting his invention. Having only a very limited amount of money with which to produce machines, yor.ng Felt, then but 24 years of age, was obliged to make the machines himself, but with the aid of some dies which he had made for some of the principal parts (see reproduction of bill for dies on opposite page), he was able to produce eight finished Manufacture of Ihr relt calculator Early Comptometer 70 Origin of Modern Calculating Machines Trade name of Felt calculator Felt calculator Exhibit at Na- ti: lA /.t/y^Y {2^f^-c/:'i.^c-^: . ■ ( /.••//^^-" ;/^//>^^;''^//.-.. //-. //./ .^. - ^ '^t/^ --2'-ci<2_ ^-^-^^^^^^-4 ^''^^■'^'^^^^^ /^^f^^-^^*-'^'^ ^' ^ «. <-.,y- ■ ^ti'J-ll^^^-i-c-^^i'^^^-^-f-^ , - v-^/>./^^/^/ //- c.,.,j Testimonial r -/■ -^fZTt-^-P ./^^i- 'eJi^'7T^-T^..-7^s/^-^^rA'r^,-<^ / / 'I'cstiiiKiiiial ^ N t ■^ ;|- :1 -^ ■> X ~x V ^" ^ ■X, V V ":' H \^ '^ $ X. ^ ^^ ■^ '': 5 > X xi 1 ^^ ^ I ^ - \\ V ^,. ^ ^" ^ X ^ :^ •j X '" •i ^^ X •- X ^> ■■u ^ ■^ ;>; \^ \. 1 ; ■^: ^ ^ tr ,^ ^^ N^ n" ■\ N ^ x^ ~> ^^ ■" ; 5 , '> 1 X ^x ^> V ^ ^? 1\ c X X X '^^ ■'S^^ " -"- :;^ V iv -- ■. ■■\ X xX is > ^ X ^^ >-^4 ^ f 1 X ^ X X ^ A ... Letters IVoiii tllliott and Kosecrans The Key-Driven Calculator 75 E. B. Elliott, Actuary of the Treasury, where it was put into constant use. Proof of the date of this use of Felt's invention in the Treasury is set forth in the reproduction of two letters (see oppo- site page) , one was written by Mr. Elliott and an- other by Gen. W. S. Rosecrans, in answer to an in- quiry of the Hall Typewriter Co. of Salem, Mass. Another of the first eight machines was placed with Dr. Daniel Draper, of the N. Y. State Weather Bureau, New York City. Felt finally closed a deal with Mr. Robert Tarrant of Chicago, whereby a partnership contract was signed November 28, 1887. The partnership was incorporated January 25, 1889, under the name of the Felt & Tarrant Mfg. Co., who are still manu- facturing and selling "Comptometers" under that name. Laying aside all the evidence set forth in the Significanl proof foregoing history of key-driven machines and " ^ scaim their idiosyncrasies, significant proof of Felt's claim as the first inventor of the modem calcu- lating machine is justified by the fact that no other multiple-order key-driven calculating machine was placed on the market prior to 1902. Lest we lose sight of a most important feature in dealing with the Art of the Modem Calculator, we should call to mind the fact that as Felt was the originator of this type of machine, he was also the originator of the scheme of operation in its performance of the many and varied short cuts in arithmetical calculation. The performance of calculation on machines of the older Art differed so entirely from the new that any scheme of operation that may have been devised for their use would lend nothing to the ij priority 76 Origin of Modern Calculating Machines Rules for opera- lion an imporl- anl factor of modern calculatcr derivation of the new process for operating the key-driven machine of the new Art. A superficial examination of one of the instruc- tion books of the "Comptometer" will convince most any one that it is not only the mechanism of the machine that made the modern calculator so valuable to the business world, but also the schemes laid down for its use. The instructions for figuring Multiplication, Subtraction, Division, Square Root, Cube Root, Interest, Exchange, Dis- count, English Currency, etc., involved hard study to devise such simple methods and rules. The instruction books written by Felt for the "Comptometer, the Modern Calculator," reflect the genius disclosed in the invention of the machine itself. From Drawings oi Harbour Patent No. 133,188 Early Efforts in the Recording Machine Art THE Art of recording the addition of columns of figures is old in principle, but not in practice. Many attempts to make a machine that would record legibly under all conditions failed. These attempts have been pointed out from time to time as the first invention of the recording -adding machine, especially by those desirous of claiming the laurels. The first attempt at arithmetical recording for first altempt to which a patent was issued, was made by E. D. ^^^o'"^ arilhmeti- Barbour in 1872 (see illustration on opposite page) . E. D. Barbour has also the honor of being the first inventor to apply Napier's principle to mechanism intended to automatically register the result of multiplying a number having several ordinal places by a single digit without mentally adding together the overlapping figures resulting from direct multiplication. He patented this machine in 1872 just prior to the issue of his arithmetical recorder patent. (See page 181.) The Barbour Machine The printing device disclosed in connection with the Barbour machine for recording calcula- tions was of the most simple nature, allowing only for the printing of totals and sub-totals. Its manipulation consisted of placing a piece of paper under a hinged platen and depressing the cal computation Origin of Modern Calculating Machines platen by hand in the same manner that a time stamp is used. The ink had to be daubed on the type by a hand operation to make legible the im- pressions of the type. Descripiion The patent drawings of the Barbour machine of Barbour ^j.^ g^ fragmentary that it is almost impossible machine ° ^ '' , .- ,. ..-, ^ to draw any conclusion as to its functions without reading the specifications. Fig. 1 represents the base of the machine, while Fig. 4 shows a carriage which, when in place, is superimposed above the base as illustrated in Figs. 3 and 5. The operation of the machine is performed by first pulling out the slides B (shown in Fig. 1), which set the digital degrees of actuation of each order; and, second, by operating the hand-lever K, from its normal position at to 1, if it is desired to add, or to any of the other numbers in accord- - ance to the value of the multiplier if multiplication is desired. The movement of the handle K, from one figure to the other, gives a reciprocation to the carriage, so that for each figure a reciprocation will take place. Each of the slides B, has a series of nine gear racks; each rack has a number of teeth ranging progressively from 1 tooth for the first gear rack to 9 teeth for the last rack, thus the pulling out of the slides B will present one of the gear racks in line to a,ct upon the accumulator mechanism of the carriage as the carriage is moved back and forth over it. The accumulator mechanism consists of the register wheels M^ and M- and the type wheels M^ Early Efforts in the Recording Machine Art 81 and M^ mounted on a common arbor and a carry- transfer device between the wheels of each order. Operating between the accumulator wheels and the racks of plate B are a pair of gears, one in the form of a lantern wheel loosely mounted on the accumulator wheel shaft but connected thereto by a ratchet wheel and pawl connection ; the other, a small pinion meshing with the lantern wheel on a separate axis, protrudes below the carriage into the path of the racks. Thus as the carriage is moved by the recipro- cating device connected with the hand-lever K, the pinions of the accumulator will engage what- ever racks have been set and the numeral wheels and type wheels will be operated to give the result. The numeral and type wheels have two sets of figures, one of which is used for addition and mul- tiplication, while the other set runs in the oppo- site direction for negative computation or sub- traction and division. A plate arranged with sight apertures covers the numeral or register wheels, while the type wheels are left uncovered to allow a hinged platen F, mounted on the top of the carriage (see Fig. 3), to be swung over on top of them and depressed. Attached to the platen F, are a series of spring clips d, under which strips of paper may be slipped (as shown by D, in Fig. 4), and which serves to hold the paper while an impression is taken. Thus the Barbour invention stands in the Art Barbour machine as something to show that as early as 1872 an "^ ^'^"^ ^^° effort was made to provide means to preserve a record of calculations by printing the totals of such calculations. 82 Origin of Modern Calculating Machines The Baldwin Machine The next effort in this class of machines is illus- trated in a patent issued to Frank S. Baldwin in 1875 (see illustration on opposite page) . The Baldwin machine is also of moment as having the scheme found in the machines known as the Brunsviga, made under the Odhner patents — a foreign invention, later than that of Baldwin, used extensively abroad and to a limited extent in this country. The contribution of Baldwin to the Art of record- ing-calculating devices seems to be only the roll paper in ribbon form and the application of the ink ribbon. The method used by Barbour for type im- pression w^as adapted and used by Baldwin; that is, the hinged platen and its operation by hand. Of the illustrations shown of the Baldwin machine, one is reproduced from the drawings of the patent while the other is a photo reproduction of the actual machine which was placed on the market, but, as may be noted, minus the printing or recording device shown in the patent drawings. Description Referring to the photo reproduction, the upper machin. ^^w of figures showing through the sight aper- tures in the casing are those of the numeral wheels which accumulate the totals, and which in the patent drawings would represent the type of the accumulator wheels for printing the totals of addition and multiplication or the remainders of subtraction and division. The figures showing below serve to register multiples of addition and subtraction which would read as the multiplier in multiplications or the quotient in division. These wheels are the type Mta JJG.3 From Drawings of Baldwin Patent No. 159,244 Baldwin Madiinc Early Efforts in the Recording Machine Art 85 wheels N, in the patent drawings, which serve the purpose of recording the named functions of cal- culation. The means by which the type wheels of the upper row are turned through the varying degrees of rotation they receive to register the results of calculation, consists of a crank-driven, revolvable drum, marked E, which is provided with several denominational series of projectable gear teeth h, which may be made to protrude through the drum by operation of the digital setting-knobs g, situ- ated on the outside of the drum. These knobs, as shown in the patent drawings, are fast to radial arms, each of which serves as one of three spokes of a half-wheel device, operat- ing inside the drum and pivoted on the inner hub of the drum. These half wheels marked F, in the drawings, by means of their cam faces h^ serve to force the gear teeth out through the face of the drum, or let them recede under the action of their springs as the knobs g, are operated forward and back in the slots X, of the drum provided for the purpose. As will be noted from the photographic repro- duction of the machine, these slots are notched to allow the arms extending through them to be locked in nine different radial positions, and that each of these positions are marked progressively from to 9. This arrangement allows the operator to set up numbers in the different orders by springing the setting-knobs g to the left and pulling them for- ward to the number desired, where it will become locked in the notch when released. This action will have forced out as many gear teeth in each Origin of Modern Calculating Machines order as have been set up by the knobs g in their respective orders. The lateral positions of the projectable gear- teeth correspond to the spacing of the type- wheels, and an intermediate gear G, meshing with each type, or register wheel, is loosely mounted on the shaft H, interposed between the said wheels and the actuating drum E, so that when the drum is revolved by the crank provided for that purpose, the gear-teeth protruding from the drum will engage the intermediate gears G, and turn them and their type or register wheels as many of their ten points of rotation as have been set up in their respective orders of the setting devices of the drum. Revolving the drum in one direction adds, while revolving it in the opposite direction subtracts, and repeated revolutions in either direction give respectively the multiple forms of addition or sub- traction which result in either multiplication or division, as the case may be. The actuating drum E, is provided with means by which it may be shifted to the left to furnish means for multiplying by more than one factor and to simplify the process of division. The means for the carry of the tens consist of a series of teeth i, formed by the bent end of a pivoted spring-pressed lever arm which is pivoted to the inside of the actuating drum with the tooth protruding through a slot in the drum, so arranged as to allow motion of the tooth in a direction paral- lel to the drum axis. Normally these teeth are held in a position to escr.pe engagement with the intermediate gears G, but provision is made for camming the teeth i, From Drawings of Pottin Patent No. 312,014 Early Efforts in the Recording Machine Art to the left into the path of an intermediate gear of one order as the type or register wheel of the lower order passes from 9 to 0. The parts which perform this function are the cam m, located on the left side of each wheel, the plunger M, which operates in the fixed shaft H, and which has a T-shaped head that, when pro- jected into the path of the carrying teeth i, serve to cam them sidewise and bring about the engage- ment referred to, which results in the higher type or numeral wheel being stepped forward one space. The cam-lugs j on the drum serve to engage and push back the T heads of the cam plungers M, after they have brought about the one-step move- ment of the higher wheel. The printing device consists of a hand-manipu- Baldwins prim- lated frame pivoted to the main frame of the machine by the shaft t. The paper is supplied from a roll about the shaft t, and an ink-ribbon is fed back and forth from the rolls u and u^ over bars of the printing-frame which protrude through slots in the casing and act as platens for the im- pression of the paper and ink-ribbon against the type. It is presumed that the paper was torn off after a record was printed in the same manner as in the more modern machines. ing mechanism The Pottin IVIachine Eight years after the Baldwin patent was issued, a Frenchman named Henry Pottin, residing in Paris, France, invented a machine for recording cash transactions, which he patented in England in 1883 and in the United States in 1885 (see illus- tration on opposite page). 90 Origin of Modern Calculating Machines First key-set crank- operated machine and first attempt to record the items in addition The form and design of the machine, as will be noted, correspond quite favorably with the scheme of the present-day cash register, although it lacks the later refinement that has made the cash regis- ter acceptable from a visible point of view. The Pottin invention is named here as the first in which two of the prime principles of the record- ing-adders of today are disclosed; one is the de- pressable key-set feature and the other is the recording of the numerical items. The Pottin machine was the first known depressable key-set crank-operated machine made to add columns of figures and the first machine in which an attempt was made to print the numerical items as they were added. Turning to the illustration of the U. S. patent drawings of the Pottin machine, the reader will note that there are four large wheels shown, marked B. These wheels are what may be called the type-wheels, although they also serve as indi- cator wheels for registering cash sales. The type figures are formed by a series of needles fixed in the face of the wheels. The means employed for presenting the proper type figure for printing and likewise the indica- tor figures to indicate the amount set up in each denominational order was as follows : Referring to Fig. 1, it will be noted that to each type-wheel is geared a spring-actuated segmental rack marked D, which, as shown in the drawing, is in contact with a pin marked i, which protrudes from the side of the depressed number (9) key. The norm.al position of the rack D, is indicated in dotted lines showing the next higher sector which has not been displaced by key depression. Early Efforts in the Recording Machine Art 91 Each key, as will be noted from Fig. 7, is pro- Description of vided with one of the pins i, which is nonnally out of the path of the lug j, as the racks D, drop for- ward ; but when any key is depressed the pin is presented in the path of the lug j, and stops fur- ther forward action of the rack. It will be noted that the arrangement of the keys is such as will allow progressively varying degrees of action to the segmental racks D. This variation, combined with the geared relation of the type-wheels and racks is equivalent to a tenth of a rotation of the type-wheel for each succes- sive key in the order of their arrangement from 1 to 9. The means provided for holding the segmental racks D, at normal, also serves to hold a key of the same order depressed, and consists of a pivoted spring-pressed latch-frame marked E (see Figs. 7 and 8). With such a combination, the depression of keys in the several orders will unlatch the segmental racks, and the racks, through the tension of their actuating springs, will turn the wheels and present a type corresponding to the numerical value of each key depressed. A hand lever, marked R, located on left side of the machine provides power for printing the items. Another hand lever, marked J, serves to restore the segmental racks, type-wheels and the keys to normal, and through the co-operation of the lever R, adds the items to the totalizer numeral wheels, which are shown in Fig. 1 as the numbered wheels marked v. PoUin machine 92 Origin of Modern Calculating Machines The paper is supplied from a roll mounted on a hinged platen frame P\ supported in its normal position by a spring P^. The paper passes under the roller P, which acts as a platen for the impres- sion of the type. A shaft Q, passing under the frame PS is fast and rigidly connected on the left- hand side of the machine with the hand lever R, and acts as a pivot for the said lever and by means of lateral projections q, serves when the lever R is operated to engage the frame P\ and depresses it until the needle types have pricked the numerical items through the paper. A slit in the casing provided means for printing the item on a separate piece of paper or bill. Although there is no means shown by which the paper is fed after an item is printed, it is claimed in the specification that the well-known means for such feeding may be employed. The actuating lever J referred to, is connected by a ratchet and geared action with the shaft F*, so that a revolu- tion is given the said shaft each time the lever is operated. To the shaft F, (see Fig. 1) is attached a series of arms H, one for each order, which, as the shaft revolves in the direction of the arrow, engages a lug marked I, on the segmental racks D, thus rock- ing the segments back to normal, turning the type- wheels with them. The return of the segment racks D, cause the back of the latch tooth f, (see Fig. 8) to engage the latch tooth f, of the latch bar E, camming it out of engagement with the keys so that any key that has been set will return by means of its own spring. *Note: All the drawings of the Pottin patent are not shown here. p .®®®®©'®®®® ®®®®®®®®® ©&©©©©©©© ©®©©®®®©.® ®®©®®©®©® ©®@®®©©®@ a ^ c^ ti ® ® ® ® ® ^{Z: (^ (^i © © ® © © ^ ■H-ijci,' (I- (i^ © @ © ® © v f^. ?2 ^? 1^1 S From Drawings of Burroughs Patent No. 388,118 Early Efforts in the Recording Machine Art 95 The total or accumulator numeral wheels are connectable with the type or indicating wheels B, by an engaging and disengaging gear motion set up by the combined action of the hand levers R and J, which first cause such gear engagement, and then, through the return of the type wheels to zero, turn the accumulator wheels, thus trans- ferring the amount of the item set upon the type wheels to the accumulator wheels. The specification claims the machine is intended for use by cashiers, bank-tellers, and others, to record receipts or disbursements. It is also claimed in the specification that instead of the needle type ordinary type may be used in combination with an inking ribbon if so desired. One of the next attempts to produce a recording- Early efforts of adder was made by Wm. S. Burroughs, whose Wm.S.Burroa,jhs name sixteen years later was used to rename the > American Arithmometer Co., now known as the Burroughs Adding Machine Co. The first patent issued to Burroughs, No. 388116, under date of August 21, 1888, like the machine of Barbour and Baldwin, was designed to record only the final result of calculation. On the same date, but of later application, an- other patent. No. 388118, was issued to Burroughs which claimed to combine the recording of the numerical items and the recording of the totals in one machine. Some of the drawings of this patent have been reproduced. (See opposite page.) Machine of Early Burroughs Patent Referring to the drawings of the Burroughs patent, it will be noted, that in outward form, the machine is similar to the Burroughs machine Will. S. Burroughs Origin of Modern Calculating Machines of today. To give a detailed description of the construction of the machine of this Burroughs patent would make tedious reading and take un- necessary space. General scheme The principle involved in the mechanism for of Burroughs' recording the items is very similar to that of the jirf inven ions pQ^-^jj^ invention ; the setting of the type wheels being effected as in the Pottin machine by means of segment gears which the depression of the keys serves to unlatch, and acts to gauge the additive degree of their movement. r^ Burroughs used the inking form of type pro- ! posed as an alternative by Pottin in his patent specification instead of the needles shown in the Pottin drawings. In the Burroughs patent, as in the Pottin, it will be noted that there are two sets of wheels bearing figures, one set of which, marked J, situated at the rear, are the type-wheels, and the other set, marked A, at the front of the machine, are for the accumulation of the totals. For each denominational order of the type and total wheels, there is provided an actuating seg- miental gear, consisting of a two-armed segmental lever pivoted to the shaft C, and having the gear teeth of its rear arm constantly in mesh with the pinion gear of the type-wheel J, and the gear teeth of the forward arm normally presented to, but out of mesh with the pinion gear of its total wheel A. Each of these denominational actuators or seg- ment gears is provided with a stop projection X-, at the top end of its forward gear-rack, which serves as a means for interrupting the downward move- ment of that end of the segment lever, and thus controls its movement as a denominational actuator. Early Efforts in the Recording Machine Art 97 It will be noted that instead of the key-stems acting directly as a stop for the denominational actuators, as in the Pottin invention, Burroughs used a bell crank type of key lever and the stop- wire C^ as an intermediate means, and in this man- ner produced a flat keyboard more practical for key manipulation. The stop-wires C\ as will be noted, are arranged Hncj description to slide in slots of the framework, and while nor- fjiy Burroughs mally not presented in the path of the stop-pro- patents jection X-, of the denominational actuators, it may be observed that by the depression of the proper key any one of them may be drawn rearward and into the path of the stop projection X-, of its re- lated actuator, and thus serve as a means to inter- cept the downward action of the actuator. The denominational actuators in the Burroughs machine were not provided with spring tension that would cause them to act as soon as unlatched by depression of the keys as has been described in relation to the Pottin invention. While the keys in the Burroughs machine, as in the Pottin invention, served also to unlatch the denominational actuators in their respective orders, no movement of the said actuators or type- v/heels took place until a secondary action was per- formed. The secondary action, or the operation of the hand lever, marked C ', attached to the shaft C, on its initial or forward stroke dragged the denomi- national actuators down by means of friction and thus set the type-wheels, and by means claimed in the specification, brought about the type impres- sion to print the result of the key-setting or the item so set. Origin of Modern Calculating Machines The backward or rear stroke of the hand lever caused the accumulator or total numeral wheels to be engaged and the item to be added to them. From this single lever action it will be noted that there is an imiorovement shown over and above the Pottin invention in the fact that but one lever motion is required; Pottin having provided two levers so that in the event of error the opera- tion of one lever would reset the machine without performing any addition or printing. In the Burroughs invention, the motion of de- nominational actuators and their type-wheels not being effected through depression of keys, as in the Pottin machine, allowed any error in the set- ting up of an item to be corrected by the resetting of the keys and relatching of the gears, which it is claimed was provided for by operation of the lever marked B^ (Fig. 1 of the drawings). As a means of supplying power to his denom- inational actuators. Burroughs provided what may be called a universal actuator common to all orders, composed of a rock frame (arms D-, loose on each end of actuating shaft C, and having their out- ward ends rigidly connected by the bar a'O and the arms E, fixed to each end of the shaft C. Projecting from the inside of each of the arms E, are two lugs, b' and b', which contact with the arms D- of the rock frame as the shaft C is rocked back and forth by its hand crank C\ and thus lower and raise the rock-frame. The means employed to transmit the reciprocat- ing action of the universal actuator to such de- nominational actuators as may be unlatched by key depression, consists of a series of spring- pressed arc-shaped levers DS pivoted to the rock- Early Efforts in the Recording Machine Art 99 frame bar a^, which bear against a pin b- fixed in the front arm of the denominational actuators. Each of the levers D^ is provided with a notch y, which serves on the downward action of the rock-frame to engage the pins b-, of the denomi- national actuators and draw down with them such actuators as have been unlatched by key depres- sion and to pass over the pins of such actuators as have not been unlatched. When in the course of such downward move- ment the denominational actuators are intercepted by the stop-wires CS the yielding spring pressure of the levers D% allow the notches y, to slip over the pins b-, and leave the denominational actuators and their type-wheels set for recording the item thus set up. The means provided for impression of the type is shown in other drawings of a patent not repro- duced here. The means provided consisted of a universal platen, which, the specification states, serves to press the ink-ribbon and paper against the type after all the figures of each item were set. \Vhile Barbour, Baldwin and Pottin all used the universal platen to print the collective setting of type represented in the items or totals, as the case may be, each varied somewhat in detail. Baldwin used a toggle to press the platen toward the type, while Burroughs used a spring to press the platen against the type and a toggle to press it away from the type. Burroughs claimed to have combined in his in- vention the printing of the totals, with the print- ing of the items, each of which it has been shown was claimed by the patentees of previous inven- 100 Oeigin of Modern Calculating Machines tions but had not been combined in one machine prior to the Burroughs attempt. The process for recording these totals in the Burroughs patent consisted of utilizing the action of the total wheels during their resetting or zero- izing movement to gauge the setting of the type- wheels. The specification shows that, during the down- ward motion or setting of the denominational actuators, as they set the type wheels, the numeral wheels are out of gear and receive no motion therefrom; and that after the recording of each item and during the return motion of denomina- tional actuators, the numeral or total wheels are revolved forward in their accumulative action of adding the items and thus registering the total. Provision is made, however, when it is desired to print the totals, to cause the totalizing wheels to enmesh with the denominational actuators on their downward or setting movement, and for the unlatching of all the racks so that by operating the hand lever C'% the downward action of the racks will reverse the action of the totalizing wheels, which will revolve backward until the zeros show at the visible reading point, where they will be arrested by stops provided for that pur- pose. By this method the forward rotation accu- mulated on each wheel will, through the reverse action of zeroizing, give a like degree of action to the type-wheels through the denominational actu- ators. Thus the registration of the total wheels, it is claimed, will be transferred to the type-wheels and the record printed thereof as a footing to the column of numerical items that have been added. Early Efforts in the Recording Machine Art » ! • < » ' > 101 » , 1 — »_» To pass judgment on the recording machines of the patents that have been described, from the invention of Barbour to that of Burroughs, de- mands consideration, first, as to whether in any of the machines of these patents the primary fea- tures of legible recording were present. The question as to operativeness respecting other features is of no consideration until it is proven that the means disclosed for recording was prac- tical. As non-recording adding or calculating ma- chines they were not of a type that could compete with the more speedy key-driven machines dealt with in the preceding chapters ; therefore without the capacity for legible recording, these patents must stand as representing a nonentity or as statu- tory evidence of the ineffective efforts of those who conceived the scheme of their makeup and attempted to produce a recording-adding machine. Without the capacity for legible recording, of what avail is it that the machine of one of these patents should disclose advantages over another? It may be conceded that there are features set forth in the Pottin and Burroughs patents that if operatively combined with legible recording would disclose quite an advanced state of the Art at the time they were patented. But credit for such an operative combination cannot be given until it exists. There is no desire to question the ingenuity dis- played by any of these inventors, but in seeking the first practical recording-adding or calculating machine we must first find an operative machine of that type; one which will record in a practical and legible manner regardless of its other quali- fications. .1// early arith- metical printing devices impractical 102 ' ' ^ ^^^ ^ ORIGIN "©F Modern Calculating Machines _fe_f r-^- Praciical method The fact that the fundamental principle used for ^""^ 'Tw/a/i the impression of the type in the practical recorder of today is not displayed in any of these inventions, raises the question as to the effective operative- ness of the printing scheme disclosed in the pat- ents of these early machines. In each of the four alleged recording-adding ma- chine patents described, it will be noted that the means employed for printing was that of pressing the paper against the group of type by means of a universal platen or plate. While with such a combination it may be pos- sible to provide a set pressure great enough to legibly print a numerical item or total having eight to ten figures through an ink ribbon, it would not be practical to use the same pressure to print a single-digit figure, as it would cause the type to break through the paper. And yet in the numeri- cal items and totals that have to be recorded in machines of the class under consideration, such wide variation is constantly encountered. We are all familiar with the typewriter and the legible printing it produces. But suppose instead of printing each letter separately the whole word should be printed at once by a single-key depres- sion, then, of course, single-letter words, such as the article "a" or the pronoun "I" would also have to be printed by a single-key depression. In this sup- position we find a parallel of the requirements oi a recording-adding machine. If it were possible to so increase the leverage of the typewriter keys enough to cause a word of ten letters to be printed as legibly as a single letter is now printed, ten times the power would have to be delivered at the type-head. Then think what # ^s% Jl i Drawings of Ludluin Patent No. 384,373 Early Efforts ix the Recording Machine Art 105 would happen with that same amount of power apphed to print the letter "a," or letter "I." You would not question that under such conditions the type would break a hole in the paper. And yet the patentees of the said described inventions wanted the public to believe that their inventions were operative. But to be operative as recording-adding machines, they must meet such variable conditions as described. It is useless to believe that a variation of from one to ten or more type could be printed by a set amount of pressure through an ink-ribbon and be legible under all circumstances. While the needle-type of Pottin may have printed the items legibly enough for a cash-register, it would not serve the purpose of a record for uni- versal use. The use of regular type and the inking ribbon proposed in his specification would bring it within the inoperative features named. The Ludlum Machine In 1888, about two months prior to the issue of the Burroughs recording machine patent just re- ferred to, a patent was issued to A. C. Ludlum for an adding and writing-machine. (See illustration on opposite page.) It will be noted by reference to the drawings that the scheme is that of a typewriter with an adding mechanism attached. The details of the typewriter may be omitted, as most of us are familiar with typewriters. A fea- ture that differed from the regular typewriter, however, was that the machine printed figures only and the carriage operated in the opposite direction, thus printing from right to left instead of left to right. Inoperative features of early recording mechanism Adding mechan- ism attached to typewriter 106 Origin of Modern Calculating Machines Description of A series of numeral wheels and their devices for machine the transfer of the tens, designed to register the totals, are shown mounted in a shiftable frame connected with the bar marked F, with the type- writer carriage, and is claimed to move therewith. Each numeral wheel is provided with a gear marked G, which, as the carriage moves after writing or printing each figure of the item, is sup- posed to slide into mesh one at a time with an adding gear marked H, the engagement taking place from right to left. Or beginning with the right or units numeral wheel a higher order numeral wheel gear is supposed to shift through movement of the car- riage into engagement with the adding gear H, each time a key is depressed. The adding gear H, is supposed to receive vary- ing degrees of rotation from the keys according to their numerical marking and to rotate the num- eral wheel with which it happens to be engaged, a corresponding number of its ten marked points "of registration. Between the adding gear H, and the keys which act to drive it, is a ratchet and gear device consist- ing of the ratchet pawl pivoted to the adding gear H, the ratchet F% and its pinion gear, the segment gear P fast to the rock shaft I, the nine arms P fast to the rock shaft and the pins P, which are arranged in the key levers to contact with and depress the arms I^ of the rock shaft varying distances, accord- ing to the value of the key depressed. That is, sup- posing that the full throw of the key-lever was required to actuate the rock shaft with its gear and ratchet connection to give nine-tenths of a revolution to the numeral wheel in adding the digit nine, the pin P in the (9) key-lever would in Early Efforts in the Recording Machine Art 107 that case be in contact with its ami I', of the rock shaft, but the pins I-, of each of the other key levers would be arranged to allow lost motion be- fore the pin should engage its arm I^ of the rock shaft, in accordance with the difference of their adding value. According to the specification, Ludlum evidently had the idea that he could stop the adding gear H, while under the high rate of speed it would receive from a quick depression of a key, by jabbing the detent J between the fine spacing of the gear teeth shown in his drawing. But to those familiar with the possibility of such stop devices, its inoperative- ness will be obvious; not that the principle pro- perly applied would not work, for its application by Felt prior to that of Ludlum proved the possi- bilities of this method of gauging additive actua- tion. The detent lever J, as shown in the drawings, is operated by the hinged plate D, through action of the key levers, as any one of them are depressed. Under depression of a key, the hinged plate D, being carried down with it, engages the arm J^ of the detent and throws the tooth at its upper end into the teeth of the gear H. The timing of the entry of the tooth of the de- tent is supposed to be gauged to enter the right tooth, but as the action of these parts is fast, slow or medium at the will of the operator, con- siderable time must be allowed for variation in the entry of the detent tooth, which requires space, as certain parts will fly ahead under the sudden im- pact they may receive from a quick stroke, where they would not under a slow stroke, but no allow- ance was provided for such contingency. 108 Origin of Modern Calculating Machines The means provided for the carry of the tens consist of the gears G'', meshing with the numeral wheel gears and the single gear tooth g^, attached to it, which, at each revolution of the lower wheel. as it passes from 9 to 0, engages the gear of the numeral wheel of higher denomination and was supposed to turn the higher gear one-tenth of a revolution, thus registering one greater. On account of the Gears G^, of one order and the gear tooth g^, of another order operating on the same numeral wheel gear, the transfer gears are arranged alternately on separate shafts, one at the side and one below the numeral wheels. Ludlum machine The mechanical scheme disclosed in the Lud- inoperative lum patent, to the unsophisticated may seem to be operative. But to those familiar with the Art of key-driven adding mechanism it will at once be obvious that even if the typewriter feature was constructed properly the possibility of correctly adding the items as they were printed was abso- lutely impossible. Laying aside several other features of inopera- tiveness, obvious to those who know such mechan- ism, the reader, although not versed in the Art of key-driven adding mechanism, will observe from the preceding chapter, that the means provided for transferring the tens without any control for the numeral wheels against over-rotation, would make correct addition impossible. The drawings and specification of the Ludlum patent disclose a mere dream and show that they were not copied from the make-up of an operative machine. It was a daring scheme and one that none but a dreamer would undertake to construct in the Eaely Efforts in the Recording Machine Art 109 method shown. There have in later years been some successful ten-key recording machines made and sold, but they were of a very different design and principle. There have also been several adding attach- ments made and sold that could be adjusted to a regular commercial typewriter that are claimed to be dependable, but none of these machines were early enough to be claimed as the first operative recording-adding machine, or the first adding ma- chine in which the principle used for the legible recording of the numerical items used in the ma- chines of today may be found. First Practical Recorders THE fact that Barbour, Baldwin, Pottin, Lud- lum and Burroughs attempted to produce a recording-adding machine shows that as far back as 1872, and at periods down to 1888, there was at least in the minds of these men a concep- tion of the usefulness of such a machine, and the fact that there were five with the same thought is fairly good evidence of the need for a machine of this class. In some of the human-interest articles issued through the advertising department of the Bur- roughs Adding Machine Co. it is stated that Wm. Seward Burroughs was a bank clerk prior to his efforts at adding-machine construction. It is con- ceivable, therefore, that his first efforts at adding- machine invention should be directed toward the production of a machine that would be of service in the bank for the bringing together of the loose items of account that are to be found in the form of checks, drafts, and the like, by printing a record of the items and their totals during the process of adding them together. It is not surprising, therefore, that a manufac- turer of a successful calculating machine should, through his contact with the trade, come to the con- clusion that there was use for a machine of this class in the banks. As proof of this, we find that an application for a recording-adding machine 111 Burroughs a bank clerk Fell interested in recorder Art tM '(W, (^ (w; (») ^ (» ^t S3 (» (5>.® (g) ® $1 ^ ^V^ From DraAvings of Felt Patent No. 405,024 First Practical Recorders 113 patent was filed January 19, 1888, by D. E. Felt, which was allowed and issued June 11, 1889. Some of the drawings of this patent will be i- til's firsi re- found reproduced on the opposite page, from ""-ding machine which the reader will note that Felt combined his scheme for recording with the mechanism of the machine he was then manufacturing and selling under the trade name of "Comptometer." In this patent is shown the first application of the type sector combined with the individual type impression for printing the figures of the items as they were added, thus giving equal impression, whether there were one or a dozen figures in the item or total to be printed. 'WTiile the average mechanical engineer would not at a glance recognize any great advantage in plac- ing the type figures directly on the sector instead of using the type-wheel and segment gear to drive it, as shown in two of the previously described patents, there is plenty of evidence of its advan- tage in the fact that all the later successful in- ventors have followed the Felt scheme. It provided more simple construction for the narrow space these parts must occupy for practical linear spacing. As the adding mechanism of this machine corres- Fell recording ponds to that of the Felt patent 371,496, previ- inechanism com' bined with his ously described in the preceding chapter, it is not calculating necessary to duplicate the description here. Suflfice "^"'^ '"^ it to say, that by the depression of a key in any order, the value of that key is added to the numeral wheel of that order, and if the figure added is great enough when added to that previously regis- tered on the wheel, a ten will be transferred to the higher wheel by a carrying mechanism spe- cially provided to allow the said higher wheel 114 Origin of Modern Calculating Machines being in turn operated by an ordinal series of keys, thus providing the means whereby a series of de- nominational orders of key-driven adding mechan- ism may be interoperative. Description of In Fig. 2 of the drawings is shown the result of ^^recordfr striking the (8) key, which may be considered illustrative of such action in any order, whether units, tens, hundreds, thousands, etc. The depression of the (8) key is shown to have carried the lever D down eight of its nine additive points of movement, causing the plunger 15, bearing against its upper edge, to drop with it under the action of the plunger spring 17. To the upper end of this plunger, is pivotally attached an arm of the type sector U, which is in turn pivoted to the rod y, and by the lowering of the plunger 15, is rocked on its pivot, raising the type-head until the number (8) type is presented opposite the printing bar or platen T, which is hung on the pivot arms T\ so that it may be swung forward and backward. An ink-ribbon w, and its shifting mechanism is provided, as shown in Fig. 1 ; the paper v, is sup- plied in ribbon form from a roll and passes between the ink-ribbon and the platen T. Normally, the platen, the paper and the ink-rib- bon are in a retracted position, allowing space for the type sector to raise and lower freely. But, as shown in Fig. 2, a type impression is taking place through the escapement of the cam wheel RV which is located back of the platen, and which, as ^shown, has forced the cam lever 1 forward, press- ing the spring p, against the platen T, thus forcing the paper and ribbon forward against the type, and printing the figure 8. First Practical Recorders 115 After the cam-tooth passes, the platen, paper, ink-ribbon and spring return to normal, allowing the type sector freedom to drop when the key is released. The cam wheel R is propelled by a spring S (Fig. 1), wound by the hand-knob S"', and is released for action through the escapement of the pallet wheel R attached to the cam wheel R and the pallet c. The pallet c is tripped each time a key is depressed and is shown in the tripped position operated by the link P and the plural-armed lever 0, N, which through its manifold arms N, may receive action through pins a, of any of the rock bars L, as they are depressed by the keys. The cycle of action described takes place with every key depressed, except that the movement of the type sector varies according to the key depressed. As the printing in this Felt invention was by in- dividualized type impression, legibility of recording as well as accurate addition was obtained. Although this patent shows that Felt had produced such an operative combination, there are two features in this patent which would prevent its becoming a marketable machine. One of these features was that of having to wind the motor spring that furnished power for the type impression. The other feature was that there was no provision for printing the ciphers. Al- though the ciphers were always omitted from the keyboard of non-recording adders, as they could perform no function in addition or other forms of calculation, they could not without inconvenience, be eliminated from items in recording. First individual- ized type impression com- bined with printing sector 116 Origin of Modern Calculating Machines First practical arithmetical recorder The first sale of a recording-add- ing machine on record The Second Felt Recorder While the last-described Felt patent was still pending, Felt improved his mechanism for record- ing, installing new features and eliminating the objectionable features referred to. These improve- ments were of such a satisfactory nature that the Felt & Tarrant Mfg. Co. made twenty-five record- ing-adders, with the new features, which were sold to various banks. The first of these machines was placed on trial with the Merchants & Manufac- turers National Bank of Pittsburgh, Pa., in Decem- ber of 1889. Good evidence of the practical features of this machine was set forth in a testimonial given at the time by W. A. Shaw, the cashier of the bank, after it had been given a six months' test. This testimonial is extant and has been reproduced on opposite page. Records show that the bank purchased that "Comptograph," which was the trade name given the Felt recording-adder, and used it until 1899, at which time this machine, along with others of the same make purchased at a later date, were re- placed by the bank with "Comptographs " of more modern type. This Felt recording machine was without ques- tion the first practical recording-adding machine ever sold that would produce legible printed records of items and totals under the variable conditions that have to be met in such a class of recording. After ten years of service this first practical recording-adding machine was still in excellent condition, and in 1907 was secured by the Compto- graph Co. from the Bank of Pittsburgh, into which the Merchants & Manufacturers National Bank, C&nWnn,t>a' lit.^.*- '/;„^-. ■/ /y/,,/:^ JLuy,.,/ y/^4f6iirM/(&J:^ f^-^:/^V<'^>C^a^-^^,:^^^t^// -t^^ ^ /If^O X^t ^^^Z^ ^ i^^^L<^ ri:^'z:^ yl^i^gi.^ ^^ -** 'P^?7>t^^^^^^^^^ Pui'cl F.-ll Hcc-nlm-niKl Listing MacliiiH". iiHJ I'scd lor 'I'cii \'ears by the Merclinnts A- Maiiufacturer.s B;i Mad, of Pittsburgh, Pa. tlic Xatiniial Museiiin at Wasliingtou First Practical Recorders 119 along with other banks, had been merged. It was finally procured by Mr. Felt and presented to the National Museum of Washington, D. C, where it may now be found on exhibit along with other in- ventions produced by Felt. A photo reproduction of this machine as it appeared before it was pre- sented to the Museum, is shown on the opposite page. Like the machine of the first Felt recorder patent, Features of first it was a visible printer, each figure being printed P'^<^i^<^°^ ^^<^<'^der as the key was depressed, the paper being shifted by the hand lever shown at the right. Unlike the former machine, however, the oper- ator was not called upon to perform the extra operation of winding up a spring to furnish power for the printing. Power for the printing was stored by the action of the paper shift-lever and an entirely different printing device was used. Provision for printing the ciphers automatically was also a feature of this machine. It was not necessary to operate cipher keys, and there were no such keys to be operated. To print an item having ciphers in it required only the omission of the ciphers as the ciphers would automatically fill in. The arrangement of the paper shows a good im- provement over the first machine, as it was more accessible, being fed from a roll at the top down and around rolls below and looped back so that it is moved upward on the printed surface, where it may be torn off as desired. The mechanism of this machine is not illustrated in any one patent. The Felt patents Nos. 441,233 and 465,255 cover the new feature, but the later patent. No. 465,255, shows it best. Some of the 120 Origin of Modern Calculating Machines drawings of the last-named patent are reproduced on the opposite page to help in explanation of the details of the new features. Description of By referring to the drawings, it will be noted ^^^^ 'recorder ^hat the form of the front of the casing differs from the machine. Other drawings of the patent, not shown here, disclose features of still later in- vention than were in the machine of the photo reproduction. But it is with the printing device that we are now interested, and it was in this patent that it was first shown in the form used in the first marketed machine referred to. The type sector marked 81 is like that of the first patent, except that it is provided with the ciphers as well as the nine digits. The cipher type are always presented for print- ing when the sectors are resting at normal. Thus, if an impression can be made without depressing the keys in that order, a cipher will be printed, as will be shown later. Back of the paper and pivoted to the rod 97, are a series of printing hammers 87, one for each type sector. The hammers are operated by the spring 88, and are shown retained against the tension of their springs by the trigger latches 89. These trigger latches are pivoted on the fixed shaft 171% and actuated by the springs 92 to cause their engagement with the notch 90 of the print- ing hammers. Each of the trigger latches are provided with a laterally extending lug 93, formed on their lower arm, and each lug overlaps the back of the lower arm of the adjacent trigger latch to the right of it, so that if any trigger latch should be operated r (No Model. 12 Sheets— Sheet 8. D. E. FELT. RECORDING COMPUTING MACHINE. No. 465,255. Patented Dec. 15, 1891. From Drawings of Felt Patent No. 40,";, 122 Origin of Modern Calculating Machines so as to extricate it from the notch 50 of its print- ing hammer, its overlapping lug 93, would cause a like action of the trigger latch to the right of that, and so on; thus releasing all the trigger latches to the right of the latch originally released. Such releasing, of course, allowed the printing- hammers 87, to spring forward in all the orders so affected. The long-stop actuating lever marked 16, corre- sponds with the lever G of the Felt key-driven calculator shown in a preceding chapter, and per- forms the same function as the rock bars L of the first Felt recorder patent. These stop levers 16 are pivoted at 17, and are provided with rear arms 86, extending upward with their ends opposite the lateral extending lug 93, of the trigger latch, which corresponds to the order of keys which the lever 16 serves. In the rear upwardly-extending end of each of these levers 16, an adjusting screw 91, is pro- vided as a tappet for tripping the trigger latch corresponding to its order. From the above-described combination of mech- anism, it may be seen that if a key in any order is depressed, it will, as it comes in contact with the stop lever 16, not only cause the adding mechan- ism to be stopped through the stop 19, but it will also, through its rear arm 86, cause the trigger latch of its order to trip, and likewise all the trigger latches and printing-hammers to the right, thus printing the figure presented on the printing sec- tor in the order in which the key was operated and the ciphers in the orders to the right in case the keys in the order to the right have not previously been operated. First Practical Recorders 123 The individual presentation of the type figures upon key depression, except for the ciphers which were normally presented for printing, required that in striking the keys, to give correct record- ing of the items, the operation must be from right to left. That is, for example, if the item to be added was $740.85, the operator would depress the (5) key in the uniis cents column, the (8) key in the tens of cents column ; the cipher in the units dollars column would be omitted, the (4) key in the tens of dollars, and the (7) key in the hun- dreds of dollars column would be struck. The printing hammers were provided with means for resetting after being tripped in the recording action. This means is connected with the paper shift-lever, so that as the paper was shifted or fed upward, ready for recording the next item, the printing-hammers were all reset and latched on their respective trigger latches, ready for a new item. Fixed to the shaft 97, on which the printing- hammers are pivoted, is a bail, marked 98, part of which is shown in the drawing, the horizontal bar of which normally lies under and out of the way of the hammers as they plunge forward in printing. And attached to the right-hand end of the shaft 97, is a crank arm connected by a link to the paper-shift hand-lever, which may be seen on the right in the photo reproduction of the machine. This connection is arranged so that depressing the lever causes the shaft 97 to rock the bail 98 rear- ward, thus picking up any tripped printing-ham- mers and relatching them. The totals had to be printed, as in the first- described Felt recorder, by depressing a key cor- 124 Origin of Modern Calculating Machines Felt principle of printing adopted by all manufac- turers of recorders Wide paper carriage for tabulating responding in value to the figure showing on the wheel in each order. The principle involved in the individual ham- mer-blow, combined with the ordinal type sector for recording in a recording-adder was new, and was the feature that has made the adding-record- ing machine of today possible, as is well in evi- dence by the presence of this combination in all the recorders that have been made by the successful manufacturers of listing or recording-adding and calculating machines. Some manufacturers have substituted a vertical moving type bar for the pivoted sector, but the scheme is the same, as the purpose is to get the arrangement of the type in columnar order, and does not change the funda- mental features of the combination which furn- ished the practical means for the individual type impression. The Felt Tabulator The next feature in the Art, that has served in the make-up of the up-to-date recorders, was the wide paper-carriage. This feature will probably be recognized by many as a means supplied for the recording of columns of items in series on sheet- paper. As will be noted, roll-paper in ribbon form had been used in all the previously illustrated and des- cribed recorders. While the Ludlum patent shows a carriage, it had no capacity for handling more than a single column of numerical items. The carriage in the Ludlum machine was a feature necessary to the tj^pewriter construction and of- fered no solution to the feature of tabulating. The first disclosure of the wide carriage feature for tabulating was in a machine made by D. E. Felt Fell Tabulat..!- Ki First Practical Recorders 127 in 1889, which he exhibited to the U. S. Census Bureau at Washington, D. C, in 1890. The ma- chine was also exhibited at the World's Fair in Chicago, in 1893, along with other products in this line of the Felt & Tarrant Mfg. Co. A photo repro- duction of this machine is shown on opposite page. The machine was left at the Census Bureau, where it was used for several weeks, and was very much liked. Felt made a contract to furnish ten machines of this type, and the machine was recom- mended for purchase by G. K. Holmes, Special Agent of the Census Bureau, but like many other government department requisitions, the purchase order was never issued. Although this feature is now found in all first- class recording-adders, the recording machine Art was too new in 1890 for the new feature to be ap- preciated, and was not pushed, as there seemed to be no demand for the wide carriage then. On this account Felt delayed applying for a patent on his invention until 1899. In 1904 a license under the patent was granted the Burroughs Adding Machine Co., but soon after the granting of the license another manufacturer of recording-adders brought out a machine with a wide carriage, which was the start of a series of long-drawn-out infringement suits. The fact that Felt had delayed taking out his patent formed the grounds on which the Court finally decided that Felt, from lack of diligence in applying for a patent, had abandoned his invention, which made it public property. The tags which may be seen tied to the carriage of the machine are the official tags used to identify it as a court exhibit during the long term of years the suits were pending in litigation. The wide paper rnrriage machine Litigation on tabulator patents latino" 128 Origin of Modern Calculating Machines Outside of the tabulating scheme, the machine was in other respects the same as the recorder just described as the roll-paper "Comptograph." 'Cross Tabu- The paper, as may be noted, is held in a shiftable carriage and is operated by two levers, one to feed the paper vertically and reset the printing-ham- mers, while the other moved the carriage laterally for the spacing of the columns of items or the cross- printing when desired. Besides the lever action for shifting and paper-feeding, means were provided on the right-hand end of the carriage for perform- ing these functions ; one of these is the thumb knob which served to feed the sheet of paper into the rolls; the other is a small lever which allows the operator to shift the carriage by hand inde- pendent of the carriage shift-lever. The Third Felt Recorder While the first lot of recording-adders manufac- tured by Felt were wholly practical, as was well proved by the statements of those who purchased them, it is easy to pick out features in their make- up that today, when compared with the new highly-developed Art, would seem to make them impractical. The necessity of operating from right to left and the necessity of printing the totals by key depres- sion were features that, in view of there being nothing better in those days, did not seem objec- tionable to those who used them. They were fea- tures, however, that Felt overcame and eliminated in the next lot of machines manufactured and placed on the market in 1890. This lot of machines, one hundred in number (a goodly number in those days), were equipped with a special hand-knob in front on the left side for I""H I I II ! I l l l j IMMWHI ENGINEERING, omitlcfir;i|)h First Practical Recorders 131 automatically printing the totals, and with means by which the ciphers were printed only on operation of the paper shift-lever, which allowed the operator to depress the keys from left to right or any way he pleased. The best evidence as to what these machines looked like is to be found in the reproduction on the opposite page of an illustration which appeared in "Engineering" of London, in 1891. It will be noted that the patent drawings of the Felt calculator are also displayed. They were used to describe the adding mechanism of the recorder. The total printing device is shown and described in patent No. 465,255, while the patent for the printing of the ciphers by the hand shift-lever was not applied for until 1904. It may be argued, and argued true, that these two later features in their generic application to the recording-adding machine Art were anticipated by Burroughs in his invention herein previously described. But, assuming that these features were operative features in the Burroughs machine, they could not be claimed in combination with a printing mechanism that was operative to give practical results and in themselves did not make the recording-adder possible. Nor was the means shown for recording the totals of use except with means for legible recording. There is no desire to discredit what Burroughs did, but let the credit for what Burroughs accom- plished come into its own, in accordance with the chronological order in which it may be proved that Burroughs really produced a machine that had a practical and legible recording mechanism. Then we will find that to produce such proof we must Fell recorder in "Engineering" of London, Eng. Total recording a Fill conibinalion 132 Origin of Modern Calculating Machines accept the fact that in all the successful recording machines manufactured and sold by the Burroughs Legible lisiing of Adding Machine Co., the printing type-sector, the iiernx and auto- printing type-hammers and the overlapping ham- maiic record mq , . -j.! j.i • i i j? j.- • x of totals first mer- triggers with their broad functioning f ea- achieved by Felt tures forming a part of Felt's invention, have been used to produce legible recording, and that the combination of practical total printing was de- pendent on Felt's achievement. We might say that broadly Burroughs invented means that could be worked in combination with the Felt printing scheme to automatically print the totals, which is in evidence in all the practical machines put out by the Burroughs Co. But such a combination was first produced by Felt in 1890, and was not produced by Burroughs until 1892. As has been shown. Felt built his recording scheme into his key-driven calculating machine, and added the paper shifting-lever to furnish the power which was utilized finally for setting the printing-hammers and tripping them for the ciphers. Such a combination divided the work, but made a two-motion machine, whereas the adding mech- anism was designed on the one-motion principle. Now the principle of the two-motion machine was old, very old. The great Gottfried Leibnitz in- vented the first two-motion calculator in 1694. (See illustration on opposite page.) The Leibnitz machine was a wonderful invention and there seems to be a question as to its opera- tiveness. As a feature of historic interest, how- ever, it created considerable commotion in scien- tific circles when exhibited to the Royal Society of London. Gottfried Wilhelm Ivcibnitz Lcihnitz Ciilfulator, made in KiOi The riist Two-Motion Macliine Desifincd to ('..nip Mullii)iicati<)n l)y 1{ (i?) iri) Q @ H) W (lii M liiii dH ii?i^ -l ® ® ® ® ® ® ® ® © ® ® ® p A --■ T I oo • From Drawings of Bollee Patent No. 556,720 The Bookkeeping and Billing ^Machine 187 hundreds drum presenting the rack for adding the multiple of 8x8 will present six teeth for the thousands wheel and four for the hundreds wheel. The rack of the thousands drum representing the multiple of 8x'7 will present five teeth for the tens of thousands wheel and six for the thousands wheel. Thus by sliding the carriage to the right one space, the numeral wheel pinions will engage first the units teeth on one drum, then the tens teeth on the next lower drum and cause the wheels to register 63152. The operator, by turning the knob G to register (4) , the next figure of the mul- tiplier, turns the drum so that a series of multi- plying racks representing multiples of 4 times each figure in the multiplicand are presented, so that by sliding the carriage another space to the right, the multiple of 4x7894 will be added to the numeral wheels. The operator then turns the knob to register three and moves the carriage one more space to the right, adding the multiple of 3x7894 to the wheels in the next higher ordinal series, resulting in the answer of 2747112. There are, of course, many questionable fea- tures about the construction shown in the ma- chine of the Barbour patent, but as a feature of historic interest it is worthy of consideration, like many other attempts in the early Art. The Bollee Multiplier Probably the first successful direct multiplying machine was made by Leon Bollee, a Frenchman, who patented his invention in France in 1889. A patent on the Bollee machine was applied for in this country and was issued March 17, 1896, some of the drawings of which are reproduced on the opposite page. 188 Origin of Modern Calculating Machines Description of Instead of using eighty-one multiplying gear Bailee Machine racks for each order as in the Barbour patent, BoUee used but two gear racks for each order ; one for adding the units and the other for adding the tens; these racks operate vertically and are marked respectively Bb and Be. (See Fig. 3.) The racks are frictionally held against gravity in the permanent framework of the machine, and are moved up and down by contact at each end, received from above by bar le, and from below by pins of varying length set in the movable plates Ab. The bar le forms part of a reciprocating frame which moves vertically and in which are slidably mounted the pin plates Ab. These plates are what Bollee called his "mechanical multiplication tables." The arrangement of the pins and their lengths are such as to give degrees of additive movement to the units and tens gear racks equal to the mul- tiplying racks in the Barbour multiplier. The pin plates are moved by the hand-knobs Ab-, and the plate shown in Fig. 3 is positioned for multiples of nine. The means for setting the multiples correspond to the index hand-knob of the Barbour machine, and consists of the crank Am, which, when oper- ated, shifts the whole series of plates laterally. A graduated dial serves the operator to set the multiple that the multiplicand, set by the position- ing of the plates, is to be multiplied by. The accumulator mechanism is mounted in a reciprocating frame which moves horizontally, causing the gears of the numeral wheels to engage first the units racks on their upstroke under action of the pins, and then the tens racks on their down- " stroke under the action of the top bar of the ver- tically moving frame, the downward motion, of The Bookkeeping and Billing Machine 189 course, being regulated by the upward movement it receives from the pin that forces it up. As may be noted in Fig. 1, the multiplying plates are held in a laterally movable carriage that is shifted through the turning of the multiplier factor setting hand crank Am, by means of the rack and pinion action. This gearing is such that each revolution moves the multiplying plates under a higher or lower series of orders, thus al- lowing the multiples of a higher or lower order series to be added in the process of multiplication or subtracted in division, as the case may be. Although the Bollee machine is reputed to be a practical machine, as is attested from the models on exhibit in the Museum of Des Arts and Metiers of Paris in France, it was never manufactured and placed on the market. Bollee's principle has, however, been commercial- Bollee s principle ized by a Swiss manufacturer in a machine made and sold under the trade-name of "The Million- aire," the U. S. patents of which were applied for and issued to Steiger. Hopkins constructed his multiplying mechanism on the Bollee scheme of using stepped controlling plates for his reciprocating racks to give the mul- tiples of the digits, but the ingenious method of application shown in the Hopkins patent drawings illustrates well the American foresight of sim- plicity of manufa,cture. During the past ten years there have been a large number of patents applied for on mechanism containing the same general scheme as that of Bollee and Steiger, but up to the present writing no machines with direct multiplying mechanism have been commercialized except "The Millionaire," which is non-recording, and "Moon-Hopkins Book- keeping Machine." commercialized . A Closing Word A S previously stated, it is impossible to de- /-% scribe or illustrate the thousands of inven- -^ -*" tions that have been patented in the Art of accounting- machines, and some of the inventors may feel that the writer has shown partiality. The subject of this book, however, has to do only with the Art as it stands commercialized and those who are responsible for its existence. In the arguments to prove validity of contribu- tions of vital importance to the Art, many other patented machines have been used which really have no bearing on the Art. But the writer was obliged to show their defects, otherwise the mis- conception derived from articles written by au- thors incompetent to judge would leave the public in error as to the real truth relative to the Art of the modern accounting machines. That all inventors deserve credit, even in the face of failure, is without question. The hours, days, months, and sometimes years, given up to the working out of any machine, intended to bene- fit mankind, whether the result brings a return or not, — whether the invention holds value, or no, — leaves a record that the world may benefit by, in pointing out the errors or productive results. If it were not for the ambitions and untiring efforts of men of this type, who give heart and soul to the working out of intricate problems, the world would not be as far advanced as it is today. 190 A Closing Woku 191 The writer has kept in close touch with the Art of calculating machines since 1893, and made ex- haustive research of it prior to that period. There have been thousands of patents issued on machines of the class herein set forth, but outside of the features reviewed there have been no broadly new ones of practical importance that have as yet proved to be of great value to the public. What is in the making, and what may be developed later, is open to conjecture. It is a safe conjecture, how- ever, that in the present high state of the Art it will tax the wits of high-class engineers to offer any substantial and broadly-new feature which will be heralded as a noticeable step in the Art. And that, as in the past, thousands of mistakes, and impractical as well as inoperative machines will be made and patented, to one that will hold real value. Index to Subjects Types of Ancient and Modern Machines Page General knowledge lacking 5 Key-driven machine.first of the modern machines 6 Recording, the primary feature of adding machines that print 7 Validity and priority of invention 8 Description of Pascal's invention 11 Constructional features of the Pascal machine 12 Increased capacity of modern calculator 13 Patent office a repository of ineffectual efforts 14 The Early Key-Driven Art First attempt to use depressable keys for adding was made in America 17 Description of Parmelee machine 18 Foreign digit adders 18 Single-digit adders lack capacity 19 Some early U. S. patents on single-digit adding machines 20 Calculating machines in use abroad for centuries 21 First key-driven machines no improvement to the Art ... 21 Description of the Hill machine 22 Hill machine at National Museum 25 Inoperativeness of Hill machine 25 High speed of key dri\-e 26 Camera slow compared with carry of the tens 26 Hill machine merely adding mechanism, incomplete as operative machine 29 Chapin and Stark patents 29 Description of Chapin machine 29 Inoperativeness of Chapin machine 30 Description of Stark machine 33 Inoperativeness of Stark machine 37 Nine keys common to a plurality of orders 37 Description of Robjohn machine 38 First control for a carried numeral wheel 41 Description of Bouchet machine 42 Bouchet machine marketed 43 Misuse of the term "Calculating Machine" 43 Description of Spaulding machine 47 Prime actuation of a carried wheel impossible in the Spalding machine 49 193 194 Origin of Modern Calculating Machines The Key-Driven Calculator Page Theory versus the concrete 50 All but one of the generic elements solved 51 Originality of inventions 51 A conception which led to the final solution 52 Evolution of an invention 55 Trials of an inventor 55 The first "Comptometer" 56 Felt patent 371,496 56 Description of Felt calculator 59 Recapitulation of Art prior to Felt calculator 60 Why Hill failed to produce an operative machine 61 Idiosyncrasies of force and motion increased by use of keys 61 Light construction a feature 62 Operative features necessary 62 Classification of the features contained in the early Art of key-driven machines 63 Carrying mechanism of Felt's calculator 63 Transfer devices 64 Carrying mechanism versus mere transfer devices 64 Details of Felt carrying mechanism 65 Manufacture of the Felt calculator 69 Trade name of Felt calculator 70 Felt calculator exhibit at National Museum 70 Significant proof of Felt's claim of priority 75 Rules for operation an important factor of modern calculator 76 Early Efforts in the Recording Machine Art First attempt to record arithmetical computation 79 Description of Barbour machine 80 Barbour machine not practical 81 Description of Baldwin machine 82 Baldwin's printing mechanism 89 First key-set crank operated machine and first attempt to record the items in addition 90 Description of Pottin machine 91 Early efforts of Wm. S. Burroughs 95 General scheme of Burroughs' first inventions 96 Brief description of machine of early Burroughs' patents 97 All early arithmetical printing devices impractical 101 Practical method for recording disclosed later 102 Inoperative features of early recording mechanism 105 Adding mechanism attached to typewriter 105 Description of Ludlum machine 106 Ludlum machine inoperative 108 First Practical Recorders Burroughs a bank clerk Ill Felt interested in recorder Art HI Felt's first recording machine 113 Felt recording mechanism combined with his calculating machine 113 Index to Subjects 195 First Practical Recorders— Cont'd. Vimv Description of Felt's first recorder. . .Ill First individualized type impression combined with printing sector 115 First practical arithmetical recorder 116 The first sale of a recording adding machine on record. . . 116 Features of first practical recorder 119 Description of Felt's second recorder 120 Felt principle of printing adopted by all manufacturers of recorders 124 Wide paper carriage for tabulating 124 The wide paper carriage machine 127 Litigation on tabulator patents 127 "Cross Tabulating" 128 Felt recorder in "Engineering" of London, England 131 Total recording a Felt combination 131 Legible listing of items and automatic recording of totals first achieved by Felt 132 The key-set principle more practical for recorders 135 Description of first practical Burroughs recorder 137 Date of use of first practical Burroughs recorder 140 Introduction of the Modern Accounting Machine Opposition to the use of machines for accounting 144 Banks more liberal in recognition 145 Improvement slow for first few years 146 The High-Speed Calculator Felt improvements on Comptometer 149 Scientific distribution of functions 150 Power consumed by old carrying method 151 Cam and lever carrying mechanism 152 One-point carrying cam impossible 153 Felt's improved method of carrying 153 Gauging and controlling prime actuation 154 Alternating stop scheme 155 Multiplex key action 156 Control of the carry by the next higher actuator 156 Forced simultaneous key action old 157 Forced simultaneity applied to a calculator impossible. . . 157 Flexible simultaneity of key action a Felt invention 158 Duplex Comptometer 159 Introduction of full-stroke mechanism 159 Error signal keyboard 160 Locking of the other orders by a short key-stroke 161 Inactive keys locked during proper key-action in cash register 161 Inactive keys not locked during proper key-action in "Comptometer" 161 "Controlled-key Comptometer" 162 The mass of recorder inventions patented 163 But few of the recorder patents of value 163 Reserve invention as good insurance 164 Erroneous advertising 164 196 Origin of Modern Calculating Machines The High-Speed Calculator— Cont'd Page Error key 166 Sub-total 166 Repeat key 166 Locked keyboard 166 Quick paper return 166 Paper stop 167 Cross tabulating 167 Item stop 167 Motor drive 168 Distinguishing marks for clear, totals, and sub-totals ... 168 Adding cut-out 168 Self-correcting keyboard 169 Split keyboard 169 Dual action keyboard 169 Non-add signal 170 Selective split keyboard 170 Selective printing cut-out 171 Grand totalizer 171 Alternate cross printing 171 Determinate item signal 172 Subtraction by reverse action 172 Selective split for keyboard 172 Rapid paper insert and ejector 172 The Bookkeeping and Billing Machine Early combinations 174 First practical combination 177 Moon-Hopkins Billing machine 177 Napier's Bones first direct multiplier 181 First direct multiplying machine 181 Description of Barbour Multiplier 182 Description of Bollee machine 188 Bollee's principle commercialized 189 A Closing Word ^ropiw^ ^^^IsHT POR^ANO.0D6,60m,>2/80^ ,^,,C BERKELEY LIBRARIF' fill liilfliilnilyiiiiiillliiiJlli ill !38802 ^;