TheCodeBreakers
The Navy's official designation of OP-20-G indicated that the agency
was the G section of the 20th division of OPNAV, the Office of the Chief of
Naval Operations, the Navy's headquarters establishment. The 20th
division was the Office of Naval Communications, and the G section was
the Communication Security Section. This carefully chosen name
masked its cryptanalytic activities, though its duties did include U. S.
Navy cryptography.
Its chief was Commander Laurence F. Safford, 48, a tall, blond
Annapolis graduate who was the Navy's chief expert in cryptology. In
January, 1924, he had become the officer in charge of the newly created
research desk in the Navy's Code and Signal Section. Here he founded
the Navy's communication-intelligence organization. After sea duty from
1926 to 1929, he returned to cryptologic activities for three more years,
when sea duty was again made necessary by the "Manchu" laws, which
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