THURAS: RECORDING SEA-WATER SALINITY 687 



SUMMARY 



A new method of obtaining a continuous record of the surface 

 saHnity of the ocean water by the measurements of the electri- 

 cal conductivity is described. The various sources of error have 

 been investigated and were mostly found to be negligible. A 

 small correction must be applied for the lack of temperature 

 compensation if a high degree of accuracy is required in the 

 salinity measurements. 



The instnunent will respond rapidly to the maximum rate of 

 change of salinity or temperature which may occur in the ocean 

 water in moving, at ordinary speeds, across the boundary of cur- 

 rents of the greatest difference in salinity. The accuracy of the 

 method is hmited by the accuracy with which the standard sea 

 water in the sealed cell is known. 



The conductivity of sea water is given throughout the range 

 of concentration found in the open ocean. 



The paper concludes with suggested applications of the salinity 

 recorder in conjunction with other recent recorders for making 

 physical oceanographic measurements. 



