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highly poisonous property "but must be restricted to places and conditions where it
is possible to exercise the strictest supervision.. Fatalities have occurred in
the United States following the use of '1080' owing to the lack of precautions.
The following experiment, which was carried out in September 1951, is
referred to here since it is a good example of the state of our knowledge and
experience in this country of the use of .1080'.
LONDON DOCKS
FIELD TESTING OF "COMPOUND 42".
Objective To investigate the relative toxic -values of "Sorexa" and
"Warfarin", the British and American Commercial products, which
are diluted forms of "Compound 42" ("Warfarin") and which have
already gained reputations as very effective rodenticides.
Method Two warehouses of similar construction and in close proximity
to each other were selected, each containing rat attractive food
cargoes» Both warehouses showed recent indications of R.rattus,
the infestation being confirmed by tracer dust and pre-baiting.
In order to discover the most acceptable dry bait base, three
types of bait were laid side by side at each bait station. These
test baits included s-
Sausage rusk
Yellow Cornmsal
Rough Oatmeal
It was soon realised that the choice of bait was dry sausage rusk,
so the other two types of bait were withdrawn from the test.
The dry sausage rusk was subsequently mixed with the "Compound 42"
in the prescribed proportion and the poisoned bait stations were
maintained over several days on the top floor only.
PART I
No. 5 WAREHOUSE - "SOHEXA".
Premises A 4-storey block warehouse of old design, superimposed over
unpaved and brick built wine vaults, situated below ground level.
The warehouse has brick walls and a paved ground floor, but the
three floors overhead are of single wood boards laid upon
transverse wooden joists which are supported on stout longtitudinal
wooden bearers carried on the full length of the walla. Each floor
is sub-divided by brick walls into 4 compartments and these are
linked by hinged steel doors, which may not be closed. The floors
are linked by a common stairway and a large conduit housing the
mechanical hoisting gears wooden cargo doors on each floor are
fitted to the external walls and many of the numerous windows are
shattered. Access to the roof is possible by way of a staircase
from the top floor terminating in a wooden door which is not secured.
In addition to these constructed accesses the longtitudinal bearers
and slight ceiling casings afford excellent rat harbourages from
where the rat population has gnawed holey in the floor boards, thub
all floors and compartments are accessible to a moving rat colony.
.Infestation Moderate evidence vjas indicated on the dusted runs of the top
and second floors, but the degree of evidence was less on the lower
floors, yet only slight evidence was indicated by the amount of
recent excreta. The infestation was recognised as a composition of
adult and young R.rattus.
Operation This was limited to the top floor, where tracking dust was laid
and thirteen test bait stations were laid. After three days of test
baiting it was decided to increase the number of station points
where the consumption of pre-bait was greatest, and substitute the
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