furture analyses. 



Samples of surface ?mter obtained enroute from Seattle to Dutch 



Plarbor were picked up from" the moving ship by teans of a buckfet lowered 



over the side. Temperatures were obtained as soon as the samples came 



aboard. Due to' the relatively small differences between the tenperaturos 



of the air„and the water, those of the latter are reliable to' within 



approximately one tenth degree centigrade, 



- ...... . 



Determination of Depth , A meter-wheel was used to determine the 

 spacing of- the sampling bottles placed on the line at definite intervals. 

 Meter-wheel readings for a vertical wire accordingly indicate"d the depths 

 of sampling but were checked for all deep stations by calculations based 

 on differences in readings of the protected and unprotected theimometers. 

 Wire angles were recorded if the line departed appreciably from the vertical 

 and these were used in conjunction with the meter-wheel readings and those of 

 the thermometers in obtaining the correct depth. Corrections' for wire angle 

 wore seldom necessary as sampling operations wore not carried out during 

 heavy v;inds. In the few cases in which samples wore obtained at odd depths 

 at individual stations, the temperature and chlorinity measurements have ^ 

 been interpolated for uniform depths to facilitate comparisons between ■:■..:■■.■ * 

 stations. 



Bottom depths were obtained at the stations by means of sonicsounding 

 (fathometer). Soundings given in the tables aire corrected for temperature 

 and chlorinity. 



T empo raturo Determination , The water temperatures at the various 

 stations were determined by means of reversing thermometers. The thermometers 

 were manufactured by Richter and Wiese and were calibrated originally by the 

 Physikalische-Technische Reichanstalt. Most of them had been recslibrated 

 ■by the United States Bureau of Standards and were checked after the cruise 

 at the Oceanographic Laboratories. Six of the eight thermometers usod were 

 graduated to 0.05° C. and could be read v/ith an error of less than 0.01° C, 

 The values for the temperatures given in the tables ara corrected readings. 

 Necessary corrections were juado according to Schumacher's formula as given 

 by SoulQ (1933). ^ 



Determination of Chlorinity , The chlor initios were all checked 

 determinations obtained by titrations with silver nitrate solution according 

 to the Mohr method. Standard sea water of the H3^drographic Laboratories of 

 Copenhagen was used as a priroary standard. The probable error of the , 

 chlorinity determination.^iis less than -^0.01 °/oo. 



Dissolved Oxygen , The dissolved oxygen was deton-;iined by nsans of 

 the Winkler (1923) method. The samples for this determination vraro secured 

 from the sampling bottles immediately after being received on deck and treated 

 at once with the necessary reagents. The final titrations were all done 

 aboard ship. 



The dissolved oxygen is reported in the tables in units of milligram 

 atoms per kilogram of water (1934). A milligram atom of an element is defined 

 as that quantity of the element which has a mass in milligrams numerically 

 equal to its atomic weight. The nutrient salts are reported in terms of 

 microgram atoms of the principle element per kilogram of sea water. A micro- 

 gram atom, abbreviated meg. at., equals one thousandth of a milligram atom. 



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