Part 22

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 drive 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 Spalding machine 47 Prime actuation of a carried wheel impossible in the Spalding machine 49

THE KEY-DRIVEN CALCULATOR 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 111 Felt interested in recorder Art 111 Felt’s first recording machine 113 Felt recording mechanism combined with his calculating machine 113 Description of Felt’s first recorder 114 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 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