.S7A- \\-ir.i.iA.M 



269 



the scale. At the end of five minutes it \\.i- -2-1 , and at the end 

 of ten minutes still 22. A number of exjriinent8 were made 

 with regard to the time necessary for the resistance coil to assume 

 the temperature of the water. Five minutes was decided on .is 

 being necessary and sufficient, and was adopted in all succeeding 

 1< wrings. 



The first lowering was to 400 fathoms, the temperature at that 

 depth being 4<>. The cable was then reeled in to 200 fathoms, 

 when the current was made. There was found to be no deflection, 

 the temperature of the water in the copper vessel having risen 

 from 40 to 48'5. This temperature agreed with that at 200 

 fathoms when lowering to the same depth. 



During the experiments there was a light south-east breeze, and 

 a very smooth sea. They lasted from 7'ls P.M. until 1 '30 A.M., 

 but special care was taken with every reading, and it is probable 

 that fifteen minutes would be a fair average time for each observa- 

 tion with the electrical apparatus. 



The results are given in the Table. 



Early on the morning of August 12th another serial t<> 

 fathoms was taken with the Miller-Casella thermometer, and 

 immediately after with the electrical apparatus. Several read- 

 ings were taken from the surface to 100 fathoms, and then the 



