32 DEPTHS OF THE OCEAN 



such precision, that it may be considered quite the equal of any 

 system adopted by subsequent expeditions. Sigsbee relates 

 that he made one day, off Havana, between 7 a.m. and 5 p.m., 

 as many as ten hauls with the dredge at depths varymg from 



Fig. 10. — Dredges. 

 a, Previous model ; fi, Sigsbee's dredge. (From Sigsbee ) 



SO to 400 fathoms. Although the bottom was unsatisfactory 

 and the dredge stuck fast every time, he managed to avoid an 

 accident and made very successful catches. He allowed from 

 three to five minutes for lowering or for hauling in a line ot a 

 hundred fathoms, and from ten to thirty minutes for the actual 



