38 



cruise between Labrador and Southern Greenland. During this post- 

 season cruise an additional 21 oceanographic stations were occupied 

 from June 25 to 29. These were disposed in the form of a single 

 section between South Wolf Island, Labrador, and Cape Farewell, 

 Greenland. On approaching Cape Farewell, sea ice was encountered 

 55 miles offshore. Because of extremely favorable conditions of wmd, 

 sea, and visibility it was possible to get tlirough the outer 30 miles of 

 the ice field before reaching ice of a character which barred further 

 progress. Consequently the innermost station was located 25 miles 

 off Cape Farewell and as we had not even crossed the Irminger Current 

 portion into the colder inshore component nothing was learned of the 

 West Greenland Current on this cruise. From previous measurements 

 it has been found that a section of the West Greenland Current off 

 Ivigtut can be mterpreted in terms of similar measurements off Cape 

 Farewell. The Ivigtut section would have been occupied in lieu of 

 the section at Cape Farewell but radio inquiries developed the infor- 

 mation that ships at Ivigtut were icebound there by the northward 

 extension of the same ice field that blocked our progress at Cape 

 Farewell. Further attempts to complete a section across the West 

 Greeidand Current were discontinued and the General Greene concluded 

 the oceanographic work of the post-season cruise. The temperature 

 and salinity data collected at the 256 oceanographic stations occupied 

 during the season and on the post-season cruise are presented in the 

 oceanographic table in this bulletin. 



The types of equipment and methods of measurement were the same 

 as in 1939. Calibration titrations and part of the supervisory work 

 was performed by Associate Physical Oceanographer Clifford A. 

 Barnes. Routine salmity bridge measurements were made by Barnes 

 and Leonard T. Quattlcbaum, fireman, second class. Other assistants 

 in the observational work were Thomas C. Crabe, yeoman, second 

 class; Alton F. Phillips, Jr., surfman, and Samuel T. Yates, seaman, 

 first class. At the 235 stations occupied during the season the extent 

 and nominal depths of the serial observations of temperature and 

 salinity were the same as in 1939. During the post-season cruise the 

 measurements at all stations extended to as near bottom as was 

 practicable. 



A program of intercomparison of the reversing thermometers was 

 carried out through periodic shifts in thermometer pairs throughout 

 the season in order to check on the functioning of the thermometers. 

 In all, 1642 individual comparisons were investigated, the probable 

 differences between the corrected readings of a pair of thermometers 

 varying among the different groups from 0.003° to 0.023° C. and 

 being 0.010° C. for the entire 1,642 comparisons. The observed 

 temperatures arc therefore considered to be accurate to 0.01° C. 



