The upper ends of the electrical leads connect with a re- 

 corder located in the ship's laboratory. Signals from the beads 

 are scanned electronically every 10 to 12 seconds, and lines show- 

 ing the depths of isotherms are printed on 19-inch-wide tape. 

 This procedure is equivalent to lowering a bathythermograph 

 every 100 to 120 feet at a ship's speed of 6 knots. Also printed on 

 the same tape are the depth of the fish at the end of the chain, 

 which is the maximum depth of observation, and the temperature 

 of the sea surface. 



With the new thermistor chain it is possible to lower a 

 string of temperature sensors into the water and then cruise 

 ahead with the string vertically suspended from the fantail. Since 

 elements are sensing from the surface down to about 800 feet 

 while the ship is moving through the water horizontally, two di- 

 mensions of coverage, depth and distance, are achieved. 



OBSERVATIONS AND DATA 

 Offshore Section 



On 11 July 1961 USS MARYSVILLE towed the chain from 

 near San Diego in a southwesterly direction (247°). Some of the 

 temperature data collected on this line from point A on figure 2, 

 31°52'N, 119°13'W (0500 on 11 July), to the end of this leg of the 

 cruise, point B, 31°22'N, 120°41'W (1830 on 11 July), are pre- 

 sented in figure 3. The incompleteness of the shallow part of the 

 record is due to malfunction of some of the shallow thermal sen- 

 sors. However, the 9°C isotherm was correctly recorded for the 

 whole of this traverse. In the figure, the vertical temperature 

 record between 250 and 550 feet is divided into three connecting 

 parts (WX, XY, and YZ). The nearshore point is W (correspond- 

 ing to A in fig. 2) and the farthest offshore point is Z (correspond- 

 ing to B in fig. 2). The horizontal scale may be considered as 

 either time or distance, and these scales are marked between the 

 sections. 



10 



