16 MARION AND GENERAL GREENE EXPEDITIONS 



to eliminate the wire angle by maneuvering the vessel. There are 

 only some few stations where the wire angle may have had any 

 important influence on the observations. These stations are as 

 follows : 



Station no. i 293.— Estimated wire angle=15° (0-500 meters) and 25° (600- 

 1,400 meters). 



Station no. i29^.— Estimated wire angle=15° (0-500 meters) and 25° (800- 

 1,600 meters). 



Station no. 1312. — Estimated wire angle about 30°. 



Station no. 1313. — Estimated wire angle about or more than 30°. 



Station no. i3J//.— About 15° (0-600 meters) and about 10° (800-2,000 

 meters). 



Station no. 1326.— About 10°. 



Station no. 1327.— About 10°. 



Station no. 1328.— About 10°-15°. 



The wire angle was taken into consideration for stations 1293, 1294, 

 1312, and 1313 and corrected in the sections of temperature, salinity, 

 and velocity, and in the dynamic calculations for the current maps. 

 This has been done simply by reducing the depths recorded by the 

 meter wheel in proportion to the mean of the wire angles for the 

 two first stations, and 30° for the two last-mentioned stations, the 

 wire being considered as a straight line. Such a method is of course 

 not accurate, but it seemed, by comparison between station curves, 

 to give more reasonable values than the uncorrected observations. 

 In the tables, however, for the four stations mentioned above, the 

 values of temperature, salinity, density, and the result of the dynamic 

 calculations are published for uncorrected depths, as measured by the 

 meter wheels. 



Approximately 1,800 soundings were taken on the 1931 cruise 

 mostly by use of the fathometer. When on the continental shelves 

 wire soundings were used to control the sonic ones. 



A brief narrative of the General Greene's 1931 cruise is contained 

 in United States Coast Guard Bulletin No. 21. 



In 1933 Nansen w^ater bottles and Richter & Wiese protected and 

 unprotected reversing thermometers were used, all of the thermom- 

 eters being equipped with auxiliary thermometers. Details of the 

 methods employed in obaining and correcting observations are the 

 same as for the 1933 season's work described by Soule (1934) (pp. 

 30-35). A series of timed trials indicated that the messengers de- 

 scended at a rate of about 150 meters per minute. No bottles were 

 reversed until at least 10 minutes after they were in place. Time 

 taken for the messengers to travel from the surface to the first bottle 

 was estimated using a speed of 200 meters per minute, and the time 

 allowed after release of the messenger from the surface, before haul- 

 ing in the bottles, was based on a messenger speed of 100 meters per 

 minute. 



The titration results gave abnormally high salinities, the values in 

 some cases being as great as 35.30%o with a small area southwest 

 of Greenland having salinities of 35.20%o or more from 200 to 

 2,000 meters. These values were so suspiciously high that several 

 thorough attempts have been made to luicover some error. Copen- 

 hagen standard water of the batch Pjs was used every daj^ in the 

 standardization of tlie silver nitrate solution, the reduction of the 

 burette reading to salinities have been cheeked, the burette and 

 pipette used have been examined, the potassium chromate solution 



