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 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