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Francis Hamilton

Automatic Sequence Controlled Calculator (Mark I)

Patent No. 2,616,626

Francis Hamilton, along with Benjamin Durfee, assisted IBM’s Clair Lake in developing the large-scale calculator conceived by Harvard’s Howard Aiken. The Mark I calculator quickly solved problems for which the manual labor had previously been enormous. Statisticians were able to work with many more variables than had previously been possible, and differential equations, integral evaluations, and problems from all areas of applied mathematics were solved with a speed and accuracy that was previously unattainable.

The Mark I consisted of 78 adding machines and calculators linked together. Hamilton was responsible for the primary organization, design, and construction of the Mark I. He and Durfee designed the circuits that correlated the operations of the device’s components into a single working unit. In collaboration with Aiken, Hamilton also designed the circuits used to compute functions including logarithms, sines, and cosines.

Hamilton also was responsible for the design of the IBM Selective Sequence Electronic Calculator, completed in 1948, which was 250 times faster than the Mark I. In 1953, he developed the IBM 650 Magnetic Drum Calculator, of which nearly 2,000 were sold – more than any electronic computer of its time. It was the first IBM computer to make a meaningful profit.

SOURCES:
IBM. (n.d.). ASCC People and progeny. Retrieved March 2014, from IBM: http://www-03.ibm.com/ibm/history/exhibits/markI/markI_team5.html

Francis Hamilton joined IBM’s predecessor Computing-Tabulating-Recording Company (CTR) as a draftsman in 1923. He collaborated with IBM engineers Clair Lake and A. W. Mills in the development of several IBM projects, and was responsible for the primary organization, design and construction of ASCC (Mark I) and the IBM Selective Sequence Electronic Calculator (SSEC) completed in 1948. The SSEC was 250 times faster than the ASCC.

Hamilton collaborated with inventor Howard Aiken and IBM engineers Clair Lake and Benjamin Durfee to build the Mark I. The Mark I was electromechanical with mechanical parts that were electrically controlled and used ordinary telephone relays that enabled electrical currents to be switched on or off. Unlike modern computers, the Mark I had no keyboard, but was operated with approximately 1,400 rotary switches that had to be adjusted to set up a run. Instructions and data input were entered into the computer on continuous strips of punch-card paper.

The Mark I was a powerful improvement over its predecessors in terms of the speed at which it performed a host of complex mathematical calculations. The Mark I could perform logarithmic and other functional table lookup and the four fundamental arithmetic operations, in any specified sequence, on numbers up to 23 decimal digits in length. Used by the Navy during World War II, the Mark I ran repetitive calculations for the production of mathematical tables that aided in aiming artillery bombs and shells. The computer also continued to assist in the solution of complex problems in various disciplines at Harvard for 15 years. Sections of the machine have been retained as artifacts at Harvard, IBM and the Smithsonian Institution.

The Mark I consisted of 78 adding machines and calculators linked together. Hamilton was responsible for the primary organization, design, and construction of the Mark I. He and Durfee designed the circuits that correlated the operations of the device’s components into a single working unit. In collaboration with Aiken, Hamilton also designed the circuits used to compute functions including logarithms, sines, and cosines.

Hamilton was also involved in the development of the IBM 650 Magnetic Drum Calculator (1953), delivered to close to 2,000 customers between the 1950s and 1960s. The quantity was more than any electronic computer sold at that time. Hamilton later became manager of the company’s Endicott Laboratory in New York in 1954. He died in 1972.

Patent Number
Year
Name

2,616,626
1952
Calculator
Co-Inventors
Clair Lake
Howard Aiken
Benjamin Durfee
*Listed for principal patent(s)
1,429,423
1922
Certificate
1,965,979
1934
Tabulating Machine
2,057,686
1936
Relay
2,086,129
1937
Mixing Valve
2,150,220
1939
Card Handling Machine
2,199,129
1940
Mixing Valve
2,234,263
1941
Data Checking Means
2,240,562
1941
Card Controlled Typewriter
2,240,563
1941
Zero Eliminating Means
2,247,915
1941
Transcribing Apparatus
2,247,916
1941
Machine for Interpreting and Printing Perforated Records
2,255,011
1941
Recording Machine
2,285,289
1942
Card Punching Machine
2,325,960
1943
Digit Transmitting System
2,328,654
1943
Punching Machine
2,348,073
1944
Sheet Stacking Mechanism
2,350,511
1944
Sheet Feeding Machine
2,366,861
1945
Card Punching Machine
2,398,014
1946
Record Punching Machine
2,403,005
1946
Typewriting Calculating Machine
2,403,006
1946
Recorder Mechanism
2,424,091
1947
Record Controlled Dividing Machine
2,451,752
1948
Record Punching Machine
2,500,269
1950
Accumulating Mechanism
2,540,029
1951
Selectively Controlled Recording Apparatus
2,540,030
1951
Selectively Controlled Recording Apparatus
2,580,768
1952
Data Look-up Apparatus for Computing or Other Machines
2,616,624
1952
Calculator
2,636,972
1953
Selective Sequence Electronic Calculator
2,641,180
1953
Zero Splits
2,700,502
1955
Multidigit Shifting Device
2,770,797
1956
Data Storage Apparatus
2,800,182
1957
Perforating Machine
2,819,457
1958
Timing and Clocking Circuits
2,877,450
1959
Data Transfer System
2,901,166
1959
Digital Computer
2,902,213
1959
Accounting Machine
2,919,429
1959
Data Transfer Mechanism
2,959,351
1960
Data Storage and Processing Machine
RE 25,482
1963
Digital Computer

Occupation: Engineer

Born: 31 May 1898

Died: 27 March 1972 in Binghamton, NY

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