The 120 machines, the U.S. Navy's Cryptanalytic Bombes, were seven feet high, two feet wide, and ten feet long. Each one weighed 5,000 lbs.
The front and back of the Bombes each had eight columns of four rotors. The top wheel mimicked the Enigma's new fourth rotor while the bottom commutator represented the rightmost, or fastest, rotor of the Enigma. The bottom rotor spun at a speed of approximately 1,725 revolutions per minute, which allowed the machine to complete its run in only twenty minutes.
This information comes from a booklet written by Jennifer Wilcox, Assistant Curator at the National Cryptologic Museum. The text of this booklet is now online.
Because so much excellent information is available through the NSA web site, I have taken the liberty of reproducing their index here. I recommend their publications as a primer of documented facts.
PDF or text file versions are available for most of the monographs and brochures. Printed copies of publications marked with an asterisk (*) may be requested from the Center for Cryptologic History via email at history@nsa.gov.
| Subject | Title | Author | Date | Available Format |
|---|---|---|---|---|
| Bombes | The Secret of Adam and Eve | Jennifer Wilcox | 2003 | Brochure |
| Cipher Machines | German Cipher Machines of World War II * | David Mowry | 2003 | Brochure |
| Code Talkers | Origins of the Navajo Code Talkers | Patrick Weadon | 2002 | Brochure |
| COMINT | A History of US Communications Intelligence during WWII: Policy and Administration * | Robert Louis Benson | 1997 | Monograph |
| Enigma | Solving the Enigma - History of the Cryptanalytic Bombe * | Jennifer Wilcox | 2001 | Brochure |
| Enigma | The Cryptographic Mathematics of Enigma * | Dr. A. Ray Miller | 2001 | Brochure |
| Holocaust | Eavesdropping on Hell: Historical Guide to Western Communications Intelligence and the Holocaust, 1939-1945 * | Robert Hanyok | 2004 | Monograph |
| Mathematics | How Mathematicians Helped Win WWII | John Clabby | 2005 | Brochure |
| Midway | The Battle of Midway: AF is Short of Water | Patrick Weadon | 2000 | Brochure |
| Pearl Harbor | Pearl Harbor Revisited: United States Navy Communications Intelligence, 1924-1941 | Frederick Parker | 1994 | Monograph |
| Pearl Harbor | West Wind Clear: Cryptology and the Winds Message Controversy - A Documentary History * | Robert Hanyok and David Mowry | 2008 | Monograph |
| SIGSALY | A History of Secure Voice Coding: Insights Drawn from the Career of One of the Earliest Practitioners of the Art of Speech Coding | Joseph P. Campbell, Jr., and Richard A. Dean | 2001 | Brochure |
| SIGSALY | SIGSALY Story | Patrick Weadon | 2000 | Brochure |
| SIGSALY | The Start of the Digital Revolution: SIGSALY - Secure Digital Voice Communications in WWII * | J. V. Boone and R. R. Peterson | 2000 | Brochure |
| War in the Pacific | The Quiet Heroes of the Southwest Pacific Theater: An Oral History of the Men and Women of CBB and FRUMEL * | Sharon A. Maneki | 1996 | Monograph |
| War in the Pacific | A Priceless Advantage: U.S. Navy Communications Intelligence and the Battles of Coral Sea, Midway and the Aleutians * | Frederick D. Parker | 1993 | Monograph |
| Women | Sharing the Burden: Women in Cryptology during WWII * | Jennifer Wilcox | 1998 | Brochure |
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Latest update August 2, 2009