readily and easily obtained by a number of casts with the bathythermo- 

 graph, and in a far more detailed manner than by the classical methods 

 of reversing thermometers. The exact depth of the thermocline is directly 

 ascertained. Much more information on the bathythermograph wiU 

 undoubtedly be given by Dr. John P. Tully, of Canada, in the paper he 

 is to present. 



The salinity-temperature-depth-recorder is a magnificent instrument 

 likewise developed at the Woods Hole Oceanographic Institution, in 

 co-operation with the Bristol Company, for the study of coastal waters 

 and the waters of estuaries where there are considerable changes in the 

 temperature and salinity gradients. During the summer of 1948 Dr. 

 Alfred C. Redfield, of the Woods Hole Oceanographic Institution, and 

 Dr. Clifford A. Barnes, of the Oceanographic Laboratories of the 

 University of Washington, used the instrument with marked success in 

 the study of waters of Washington Sound, which includes the San Juan 

 Archipelago in the State of Washington. These waters are characterized 

 by cold oceanic water that has been upwelled off the coast of Washington 

 and British Columbia and is carried through the Strait of Juan de Fuca 

 northward into Washington Sound. From the north there flows during 

 the summer months the much warmer surface waters from the Strait 

 of Georgia, which represent dilution by the Fraser River. The instrument 

 has also been used by the Oceanographic Group attached to the Pacific 

 Biological Station at Nanaimo, British Columbia, for the study of the 

 waters of the estuaries of the west coast of Canada. 



The instrument consists of a submersible " head " containing the 

 measuring elements assembly and a deck mechanism fitted with a com- 

 puting and amplifying system for " processing " and recording the 

 measurements. The " head " can be lowered to depths of nearly 200 

 metres. It contains a resistance thermometer to measure the temperature, 

 electrodes for conductivity, and a Bourdon tube element for pressure. 

 These instruments continuously relay the measurements to the deck 

 mechanism, which computes salinity from temperature and conductivity 

 and translates pressure into depth. The temperature and the mechani- 

 cally computed readings of salinity and depth are recorded simultaneously 

 in lines of different coloured inks on a synchronized paper-strip chart. 

 Temperature with the present instruments available can be measured 

 over a range from —2-0° c. to 32° c. with an error not exceeding 0T° c. ; 

 salinity throughout a range of 20°/oo to 40°/oo with an error not exceeding 

 0-3°/oo. The maximum depth error is approximately 2 metres over the 

 range of 185 metres. 



Vertical profiles of water structure can be taken by lowering the 

 sensitive head of the instrument from a drifting vessel. By towing the 

 head of the instrument just below the surface a horizontal view of the 

 water structure can be obtained along a ship's course. The quick 

 response and the continuous recording features of the S-T-D adapt it 

 particularly to obtaining the overall pattern of water structure and 

 thermal changes in coastal waters. 



Coring Devices : Mention should also be here made of the several 

 forms of apparatus used in securing long cores from the floor of the 

 ocean depths and which are bound to play an important role in geological 

 exploration. The first successful device for securing long cores showing 

 the structure of the ocean floors was developed by Dr. Charles S. Piggott, 

 formerly of the Geophysical Laboratory of Washington, D.C. Very 

 recently Dr. Kullenberg, following suggestions of Dr. Hans Pettersson, 



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