156 • DOLLIS HILL
when required to the prime minister. The limits of the director-gener-
al’s responsibilities were set out by theMaxwell Fyfe Directive, is-
sued by the home secretary in September 1952 and published for the
first time byLord Denningin September 1963. Until the appoint-
ment ofStella Rimingtonin February 1992, the name ofMI5’s di-
rector-general was unannounced and the subject of aD Notice.
The director-generals have beenVernon Kell(1909–40),David
Petrie(1940–46),Percy Sillitoe(1946 –53),Dick White(1953–
56),Roger Hollis(1956–65),Martin Furnival Jones(1965–71),
Michael Hanley(1972–79),Howard Smith(1979–81), John Jones
(1981–85),Antony Duff(1985–87),Patrick Walker(1987–92),
Stella Rimington (1992–96),Stephen Lander(1996 –2000), and
Eliza Manningham-Buller(2000–05).DOLLIS HILL.Originally part of a government radio-location sys-
tem, linked to Burnham and Baldock, the Post Office Engineering
Research Station at Brook Road, Dollis Hill, North London, was the
location of some of the most innovative experimental work under-
taken before and during World War II on behalf of the Security Ser-
vice, including the development of telephone tapping equipment and
covert microphones. In 1941 it was under the direction ofTommy
Flowers. The engineering staff had previously concentrated on high-
speed electromagnetic switching gear for telephone exchange, but ef-
fectively becameGCHQ’s technical laboratory. The researchers at
Dollis Hill developed the world’s first programmable analog com-
puter, codenamedcolossus, destined forBletchley Park. The site,
once part of Neasden golf course, was considered so secure that an
alternative Cabinet War Room, codenamedpaddock, was built deep
underground.
DOMESTIC AGENTS.The Security Service has always attempted to
recruit staff working in foreign diplomatic missions in London, and
domestic servants have proved useful, especially during World War
II. A civil servant in the Ministry of Labour, Jimmie G. Dickson, was
attached toMI5for the duration of hostilities to assist in identifying
suitable candidates for cultivation. An MI5 report in 1945 noted:
Servants in the embassies are not in a position to obtain high quality intelli-
gence. They can provide details on the social life of the mission and some