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Mark I Renovated Exhibit — Photo #1
Photographed in April 2014

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Mark I Renovated Exhibit — Photo #2
Photographed in April 2014

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Mark I Renovated Exhibit — Photo #3
Photographed in April 2014

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Mark I Renovated Exhibit — Photo #4
Photographed in April 2014

In the spring of 2014, seventy years after Mark I's first arrival at Harvard, a renovation of the permanent exhibit reinterprets the machine's significance from a 21st century perspective.

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Mark I is unique among early computers for being one of the few still in existence. Finished with a sleek, futuristic exterior, it was constructed for reliable, round-the-clock operation during World War II. Even as much faster vacuum tube and transistor computers arrived on the scene, researchers and engineers continued to use the computer well into the 1950's.

During the war, Mark I operated day and night in the basement of the Cruft Laboratory. After the war it served as the cornerstone for a new center in the emerging the field of computer science, Howard Aiken's Computation Laboratory. Although it continued to compute problems for the Navy, by the end of the 1940s it was transferred completely for use in university projects, where students increasingly took charge of the machine.

By the time of its retirement in 1959, Mark I's historical significance was a widely known. When it went offline, the original computer was divided into several parts to be exhibited in different locations and smaller spaces around the world.

The largest section remained at Harvard on permanent exhibition. The specimen on display was shortened to half its original length by making each section smaller: half of its constant switches and counters were taken away; one of the interpolators, the multiplication unit, and several of the original card-reading and punching mechanisms were also removed.

In contrast to how Mark I looked when it was fully operational, the exhibit version is considerably shorter in depth, as the multiplication units that were removed extended perpendicularly several feet behind the machine. Additionally, while in use several walls of racks holding paper tapes extended behind the computer. While the Mark I cannot work as a calculation device anymore, the exhibit version maintained the function of its mechanical parts, which can still be set in motion with an electric motor.

As for the remaining pieces of Mark I, most of the units removed from the computer were re-assembled as an exhibit at the Smithsonian Institution's National Museum of American History, which was on public view for about two decades. These parts remain in storage at the Smithsonian Institution. One of these sections is now on loan as a permanent exhibit at the Nixdorf Computer Museum in Paderborn, Germany. The remaining components were taken back by IBM, where they are kept in storage.

After it retired from service and began a life on display, the original Mark I exhibit at Harvard was located in the Computation Laboratory, where it remained until that building was replaced by the Maxwell-Dworkin in the mid-1990s. Mark I was then relocated to its present location in the Science Center building, where a permanent exhibit was built in 1997 by the Collection of Historical Scientific Instruments in collaboration with Professor I. Bernard Cohen and Robert Campbell, one of Mark I's original programmers. In 2014, the permanent exhibit underwent an extensive renovation to showcase the machine's pioneering contributions to the enterprise of computing.


The Collection of Historical Scientific Instruments

Peter Galison, Joseph Pellegrino University Professor & Faculty Director
Jean-Fran├žois Gauvin, Director of Administration & Lecturer
Sara J. Schechner, David P. Wheatland Curator
Martha Richardson, Collections Manager & Registrar
Sara Frankel, Assistant Collections Manager
Samantha van Gerbig, Designer & Photographer
Michael Kelley, Technology & Applications Coordinator
Richard Wright, Curatorial Technician

Exhibit Curators & Content Supervisors
Laura Neuhaus, Wheatland Curatorial Fellow (CHSI)
Juan-Andres Leon, Project Manager (CHSI)

Image Credits
Collection of Historical Scientific Instruments
Harvard University Archives
Smithsonian Institution Archives Center
U.S. Library of Congress
Popular Mechanics
Time Magazine Inc.

Exhibit Design & Construction
Paul Montie, Paul Montie Design
Jonathan Hondorp, Aries Custom Works
Dale Parker, Advanced Imaging

Mark 1 Operation
Wolfgang Rueckner

Mark 1 Film - Cinematography and Editing
Maria Stenzel, mariastenzel.photoshelter.com

Website Designer
Cira Louise Brown, Wheatland Curatorial Fellow (CHSI)

1997 Exhibit Credits
I. Bernard Cohen
William Andrewes
Robert Campbell

Science Center Operations
Andrew Laplume, Building Manager
Chris McNeill, Building Services Coordinator

Special Acknowledgments
Paul Ceruzzi, Smithsonian Museum of Air and Space
Peggy A. Kidwell, Smithsonian Museum of American History
Kay Peterson, Smithsonian Archives Center
Stephanie Dick, Wheatland Curatorial Fellow (CHSI)
James Bergman, Wheatland Curatorial Fellow (CHSI)

Support Generously Provided By
The David P. Wheatland Charitable Trust
Anonymous donor

Collection of Historical Scientific Instruments   © President and Fellows of Harvard College