44 THE PROBLEMS OF THE DEEP SEA r 



off the coral, which is brought up entangled in th( 

 cords. A similar contrivance has arisen out of th( 

 necessities of deep-sea exploration. 



In the course of the dredging of the Porcupine 

 it was frequently found that, while few objects o 

 interest were brought up within the dredge, man] 

 living creatures came up sticking to the outside o 

 the dredge-bag, and even to the first few fathom* 

 of the dredge-rope. The mouth of the dredge 

 doubtless rapidly filled with mud, and thus the 

 things it should have brought up were shut out 

 To remedy this inconvenience Captain Calve] 

 devised an arrangement not unlike that employee 

 by the coral-fishers. He fastened half a dozer 

 swabs, such as are used for drying decks, to th( 

 dredge. A swab is something like what a birch- 

 broom would be if its twigs were made of long 

 coarse, hempen yarns. These dragged along aftei 

 the dredge over the surface of the mud, and en- 

 tangled the creatures living there multitudes oi 

 which, twisted up in the strands of the swabs 

 were brought to the surface with the dredge. A 

 further improvement was made by attaching 2 

 long iron bar to the bottom of the dredge bag, and 

 fastening large bunches of teased-out hemp to the 

 end of this bar. These " tangles " bring ujc 

 immense quantities of such animals as have long 

 arms, or spines, or prominences which readily 

 become caught in the hemp, but they are very 

 destructive to the fragile organisms which thej 



