32 



which were kindly loaned for the season by the Woods Hole Oceano- 

 graphic Institution ; and 2 unprotected thermometers which were made 

 available for our use during the season by the United States Bureau of 

 Fisheries. Two of the above-mentioned group of 11 were lost on 

 June 4 with the defective bottle; and 2 new unprotected thermometers 

 were received from the Champlain on June 21 and hence were available 

 for use on the northern cruise. All of these deep-sea reversing ther- 

 mometers w^ere of Richter & Wiese manufacture. In addition to this 

 equipment there was a salinometer or Wenner salinity bridge (the first 

 Coast Guard instrument described in U.S. Bureau of Standards R.P. 

 223); a Knudsen titration outfit; sample bottles; meter-wheels, etc. 



At the 25 stations taken during the season the observations extended 

 to a depth of about 1,000 meters where the depth of water permitted. 

 It was attempted to obtain observations at the levels of 0, 25, 50, 75, 

 100, 150, 200, 300, 400, 600, 800, and 1,000 meters. After the actual 

 depths at which the observations were made had been determined, 

 vertical distribution curves of salinity and temperature were drawn 

 and values were scaled from the curves at the levels mentioned. The 

 dynamic calculations were then made from these scaled values. The 

 number of water bottles sent down on any one series was usually not 

 greater than seven. Most of the water bottles carried two protected 

 thermometers each; but the deepest bottle of a series carried one pro- 

 tected and one unprotected thermometer. At stations where two 

 series were necessary, both the uppermost and deepest bottles of the 

 deep series carried an unprotected thermometer. No bottles were 

 reversed until at least 10 minutes had elapsed after the bottles were in 

 place. After being hauled to the surface the thermometers were 

 allowed a minimum of 20 minutes to attain equilibrium with the air 

 before they were read. Temperatures were read by members of the 

 crew and checked by either the oceanographer or his assistant. Read- 

 ings were taken to the nearest Koo° with a magnifying glass and were 

 corrected by means of individual graphs such as are described in the 

 Hydrographic Review, volume X, no. 1, May 1933, pages 126-130. 

 The thermometers were used in pairs and were periodically shifted with 

 respect to each other so that each thermometer had many intercom- 

 parisons with other thermometers. At the end of the season these 

 intercomparisons were examined and where shifts in the zero-point 

 were indicated the further necessary corrections to the temperatures 

 were made. It is considered that the observed temperatures are 

 accurate to 0.02°. 



Whenever conditions seemed favorable, that is when there was little 

 wind and a small wire angle, opportunity was taken to check the pres- 

 sure coefficients of the unprotected thermometers both during the 

 season and on the northern cruise. The pressure coefficients so ob- 

 tained were based on the assumption of an accurate meter-wheel and 



