46 



ance to the water, both 

 hauled in. It is, 

 besides, quite use- 

 less for towing, for 

 which purpose it 

 was never intended. 

 In the construction , 

 of our nets on the 

 "Michael Sars" our 

 idea was to make 

 the fore part in such 

 a way that as much 

 water as possible 

 might percolate 

 through. As a rule 

 they are i metre in 

 diameter at the 

 entrance and 4.5 

 metres long (see 

 Fig. 29). The fore 

 part is cylindrical 

 for a length of ij 

 metres and of the 

 same size as the 

 entrance. There is 

 first half a metre of 

 shrimp net, then i 

 metre of coarse silk 

 with a mesh of 12.5 

 mm., and the after 

 part, consisting of a 

 cone, 3 metres long, 

 of finer silk with a 

 mesh of 0.8 mm. 

 These filter the 

 water admirably. 

 We can tow them 

 at a great speed and 

 haul them on board 

 rapidly, even with 

 the little after star- 

 board winch ; and 

 they capture young 



DEPTHS OF THE OCEAN 



while being lowered and while being 



'-^'^fdj 



Fig 29 -The "Michael Sars" Tow-Net. 

 A, net ; B, coarse silk ; C, finer silk ; D, lead. 



