35 
B FIRST SECTION OF THE VOYAGE 
1 Chemistry (G, Weichart) 
Chemical parameters also served the purpose of 
characterization of the different watermasses, apart 
from temperature and salinity (see Contribution No, 
384 du Departement Scientifique, Centre Oc&anologique 
de Bretagne), During the cycle sections 2 and 6, the 
chemistry working team of the Deutsches Hydrographi- 
sches Institut determined the dissolved silicate, 
the dissolved inorganic phosphate, and the dissolved 
oXygen, 
The water samples were taken by a Bissett-Berman probe, 
Twelve water samplers were attached to this probe, and 
they could be closed - at the water depths desired —- 
by remote control from on board ship. 
The determination of the dissolved si 1 i- 
ca te was carried out with a Technicon Company 
Auto-Analyzer II, according to the silicomolybdenum 
blue method, as recommended in the firm's analysis 
instructions, 
Ammonium molybdate solution: 1 % ammonium 
in 0.1 N sulphuric acid, 
Flow rate: 0.51 ml/min, 
Oxalic acid solution: 5 % oralic acid in distilled 
water. 
Flow rate: 0,38 ml/min, 
Ascorbic acid solution: 1,76 % ascorbic acid 
distilled water. 
Flow rate: 0,39 ml/min. 
Flow rate of the seawater to be inve.tigated; 
0.38 ml/min, 
Time of passage of the seawater through the whole 
system (from the sample taker to the cuvette): 
ca, 8 min, 
No. of samples per hour: 10, 
Calibration substance: sodiumfluv--- 
vybdate 
ıte (Na„SiFc).