dle
additional fuel at some point during the 3,000-mile cruise,
&
i
The proposed track finally was laid out on a grid (Fig. 7)oe :
providing distances of 45 miles betweenstations.
Track lines ve i
running northeast and southwest, although calling for longer
aa
i
runs between stations than on north-south or east-west tracks,
-#-
appr
ing.
abou
plar
shir
were used (a) to give continuous water monitoring readings that
futi
were only 32 miles apart, and (b) to put the operations at sea
7
‘
SpaethGil! Sle ge ow snAaahi-sallthalnieoe
on headings that would minimize the ship's roll.
A 5!
Buc
The Actual Track: From the point of the initial drop to gates
. gas
ee
aes
the return to Eniwetok for fuel on June 1€, the WALTON followed"
rather closely the track that had been laid out in advance.
.
Pre
During the second half of the cruise, however, it was necessary ~.-
to modify the track to avoid possible contamination of the ship
4
by tests scheduled in the area and to provide, in the vicinity Es
a more complete coverage of the area contaminated by *S
the drift of radioactive materials.
‘The track actually accom~ im.
yB-
of Bikini,
ee
plished by the WALTON is shown in Pigure 8.
COLLECTION AND PREPARATION OF SAMPLES
Plankton, water, and fish samples and continuous measure
ments of the activity in the surface water were taken.
Plankton Samples and Water Temperatures:
Plankton samples
were obtained by twenty-minute oblique tows from about 200
meters of depth using a l-meter Michael Sars type net of No. 63
mesh (Fig. 3).
No. 6 mesh is equivalent to seventy-four meshes..:
per inch with apertures of 0.24 mm.
This mesh retains some
microplankton as well as larger forms.
Organisms longer than
ty,
e
¥
wat
Bi
th:
ca
vi
tt
a?