The UK Biological Weapons Program - Deadly Cultures: Biological Weapons Since 1945 - page 57

named Operation Cauldron, took place from May to September 1952 off
the Scottish island of Lewis, in the Outer Hebrides. Scientists tested the
agents responsible for plague and brucellosis during the trials, and now
employed a far more manageable experimental apparatus than that used
in Harness.
The Ben Lomond was the only ship involved, acting as both the clean
and dirty vessel. A 200-by-60-foot floating pontoon, described as “little
more than a floating box with 24 compartments, 9 of which had to be
converted to house diesel generators, pumps, 'clean' and 'dirty' animal
stowage, change rooms, &c,” was the focus of the experimental tests. The
experimenters placed their guinea pigs and monkeys in cages on the sur-
face of the pontoon, with a few naval and civilian personnel in protective
gear retreating into the compartments below, and the test bomb (or in
some cases spray) was detonated from a boom holding the munition
some 25 feet away. Timing the detonation proved to be no easy task, and
the report of the trial noted that “determination of the exact moment of
release is important and difficult ...acouple of seconds can make the dif-
ference between success and failure.” 37 The exposed test animals were
then taken on board the Ben Lomond, where, after several days, scientists
carried out postmortems on animals that had died during the holding pe-
riod and on some that were sacrificed at the end of this period. During the
trials 3,492 guinea pigs and 83 monkeys were used in this manner. Hu-
mans as well as other animals ended up being exposed in these trials. On
the last day of Cauldron, a fishing vessel, the Carella, strayed into the path
of a trial using plague. 38 The trawler was tailed by two naval vessels for 21
days, waiting for any distress call. When none came, almost all records of
the incident were burnt.
The trial report concluded that good results had been obtained for
Brucella suis, “new ground had been broken with plague trials,” and the
pontoon technique had been a success. A year later, this assessment was
contradicted by the BRAB. Apart from the utility of the pontoon, other
results were now seen as less promising. Fildes, with the general agree-
ment of his colleagues, declared that the test of plague had been a “fail-
ure” and that brucellosis “had not increased its reputation as a dangerous
agent.” 39
The following year saw a return to Lewis for Operation Hesperus. This
series of trials encountered terrible weather and was eventually judged to
have been “productive of experiments and less productive of positive