DIRECTION FINDING• 153DIPLOMATIC SECTION.TheGCHQbranch responsible for decryp-
ting the Foreign Ministry wireless traffic of target countries, headed
from 1942 by CommanderAlastair Dennistonand located in offices
above Peggy Carter’s hat shop in Berkeley Street, London. The Dip-
lomatic Section’s first successes included traffic from Sofia to Berlin,
Ankara to London, London to Madrid, London to Lisbon, Kuibyshev
to Ankara, and Bucharest to Tokyo.
Before World War II the Diplomatic Section had broken the Greek,
Portuguese, Spanish, Italian, Persian, and American diplomatic
codes, which were circulated to authorized recipients asBJs. The
section’s greatest success was against the German Foreign Ministry
one-time padsystem, codenamedfloradora. In 1943 the most se-
cret subsection of the Diplomatic Section, headed by Bernard Scott
and working on traffic codenamediscot, was accommodated in of-
fices on the sixth floor ofAllford House, on Rak Lane, where work
on Russian ciphers was concentrated in a group of less than two
dozen, including Felix Fetterlein.
DIPLOMATIC WIRELESS SERVICE (DWS).Created in 1945 as
an amalgamation ofSection VIIIof theSecret Intelligence Service
(SIS) and the Radio Security Service (MI8), the Diplomatic Wireless
Service is located atHanslope Park, an estate purchased in 1939 as
a wireless receiving station for the Foreign Office. As well as super-
vising the communications of the Foreign Office, the DWS accom-
modates specialist workshops to develop and provideMI5and SIS
with equipment not available on the open market. Because of the na-
ture of its work, DWS has long been a target for penetration, although
only one case of espionage, that ofWilliam Marshallin 1952, has
been discovered.
DIRECTION FINDING (D/F).The technique of triangulating wire-
less signals so as to locate their origin. Direction finding is a valuable
intelligence aid even if the traffic itself cannot be read. The British
D/F network during World War I, pioneered by AdmiralSir Reginald
Hall, consisted of 19 receiving stations known as ‘‘directionals’’
linked to a central plotting room in the Admiralty, which successfully
monitored the movements of enemy U-boats andZeppelins. During
World War II, much of the D/F burden fell on the Admiralty’s Shore