MIND UNDER WATEB. 161 



ably believed to be very audible indeed to the jack. 

 The wire fences which are now so much used round 

 shrubberies and across parks give a very good illus- 

 tration of the conveyance of sound. Strung tight by 

 a spanner, the strands of twisted wire resemble a 

 stringed instrument. If you place your hand on one 

 of the wires and get a friend to strike it with his 

 stick, say, thirty or forty yards away, you will dis- 

 tinctly feel it vibrate. If the ear is held close enough 

 you will hear it, vibration and sound being practically 

 convertible terms. To the basking jack three such 

 wires extend, and when the cart-horse in the meadow 

 puts down his heavy hoof he strikes them all at once. 

 Yet, though fish are so sensitive to sound, the jack is 

 not in the least alarmed, and there can be little doubt 

 that he knows what it is. A whole herd of cattle 

 feeding and walking about does not disturb him, but 

 if the light step — light in comparison — of a man 

 approach, away he goes. Poachers, therefore, unable 

 to disguise their footsteps, endeavour to conceal them, 

 and by moving slowly to avoid vibrating the earth, 

 and through it the water. 



In poaching, the intelligence of the man is backed 

 against the intelligence of the fish or animal, and the 

 poacher tries to get himself into the ways of the 

 creature he means to snare. That is what really takes 

 place as seen by us as lookers-on ; to the poacher him- 

 self, in nine out of ten cases, it is merely an acquired 

 knack learned from watching others, and improved by 

 practice. But to us, as lookers-on, this is what occurs : 

 the man fits himself to the ways of the creature, and 

 for the time it becomes a struggle between them. It 



