in the Twenty Years before 1895 



49 



soundings in 2000 fathoms of water can be made in an hour from 

 start to finish, but in order to do this the wire must be hove in 

 ist as possible and breakages frequently occur. When the 

 \\ire carries deep-sea thermometers or other valuable instru- 

 ments, it is impossible to work at this rate with any regard to 

 the safety of the instruments. With hemp line the maximum 

 rate of working can be observed whether the line carries 

 instruments or not, because, if the line has been properly 

 cared for, breakages do not occur. 



The following short table shows the ordinary rate at which 

 deep soundings were carried out on board the "Challenger": 



With regard to the dredge or trawl line, when clear of the 

 in it was brought up from 3000 fathoms at the average 

 rate of 1000 fathoms per hour. 



In pointing out the good fortune that it was for the 



illenger" that she was fitted with lump sounding and 



iiiL,' lines, it must not be supposed that these lines can 



be allowed to take care of themselves, and that they guarantee 



safety of the instruments attached to thnn. < >n 



rary, deep-sea sounding lux must, to begin with, be made 



i< ntiously out <f th< very best long-fibred hemp, and 



tin- tii: first used until the day it is condemned 



as being worn it has to be most carefully attended to, especially 



B. III. 4 



