b. Conductivity bridge 

 salinometer (Univer- 

 sity of Washington) 



Electrical nnethod - -conductivity cell 



a. Foxboro Company 



b. Serfass Bridge 



Salinity accuracy: ±0.005%o. 

 Repeatibility: ±0.001%o. 



DEPTH 



Unprotected mercury thermo- 

 meter 



Mechanical pressure trans- 

 ducer (Bourdon tube, 

 bellows, helical coil, 

 aneroid, etc . ) 



Electronic pressure trans- 

 ducer ( "Vibratr on, " strain 

 gauge, variable reluct- 

 ance , etc. ) 



Accuracy: ±0.1%o. 



Accuracy: ± 1 . 0%o (0. l%o if 

 calibrated before and 

 after use). 



Probable error of depths: 

 *15 ft. for depths less 

 than 3, 000 ft. ; at greater 

 depths to about 0. 5%. 



Depth: to 1, 500 ft. 



Accuracy: ±15 ft. 



Depth: to 1, 500 ft. 



Accuracy: ±4 ft. 



(Accuracy of the system 

 is generally limited by 

 the recording apparatus. ) 



CURRENT 



Mechanical current meter 

 (Ekman) 



Speed: 0. 15 to 2. 5 knots. 

 Accuracy: ±0. 1 "knot. 

 Direction: to 360°. 

 Accuracy: ± 10°. 



Electro-miechanical current 

 meter 



1. Price meter 



Speed: 0.1 to 6.5 knots, 

 Accuracy: *0.1 knot. 

 Direction: None. 



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