32 



HALF AN HOUR WITH PREPARATIONS. 



facts in a way 

 you will never 

 forget. In- 

 deed, there is 

 nothing like a 

 night or two's 

 outing with 

 the trawl-boats 

 for introducing 

 you to marine 

 zoology. The 

 following is 

 the principle 

 on which that 

 useful object, 

 the trawling- 

 net, is con- 

 structed. 

 There is a 

 large iron head 

 (a) attached to 

 a beam, as in 

 the accom- 

 p a n y i n g 

 Figure 6. To 

 the latter the 

 net is fastened, 

 its end ter- 

 minating in 



