286 OUT OF DOORS. 



surface, they may usually be induced to do so by 

 driving the prongs of a garden-fork into the ground 

 and working it about so as to shake the earth around ; 

 and, if they still should be obdurate, they may be 

 brought to light by pouring over the ground some water 

 in which a very little ammonia has been dissolved. 



Not only the river fishes, but those of the saltwater 

 can be reared from the earliest stages, and kept in 

 ponds and fattened just like chickens, only with much 

 less trouble and expense. Even the flat fishes are 

 capable of being thus fattened, and become wonderfully 

 thick in body and firm in flesh, so that their weight is 

 really astonishing when it is compared with their length. 

 The food which they require is of the cheapest kind, 

 and the fattened fish can be sold for so high a price as 

 to render the speculation extremely remunerative. 



A few lines must be given to the machine in which 

 fish can be conveyed for great distances without sufi'er- 

 ing damage or perishing for want of air. It consists, 

 as may be seen from the accompanying illustration, of 

 a square metal box closed above with a cover of per- 

 forated zinc. The box is not nearly filled with water, 

 so that there is little fear of the contents being splashed 

 out by the shaking incident to all travelling. The fish 

 congregate at the bottom, and would soon exhaust the 

 air contained in the water were it not renewed by 

 artificial means. 



In one comer of the box is placed a forcing-pump, 

 neatly fitted ip with appropriate valves, and communi- 



