202 THE OCEAN. 



fish, however, are of constant observation within the 

 tropics, it seems but natural to conclude that they 

 are but the frolicsome putting forth of superabundant 

 animal energy ; that they are, in fact, performed in 

 sportive play, as the lamb skips and leaps upon the 

 grass, or the dog pursues its own evasive tail. 

 These flights, generally performed in shoals varying 

 in number from a dozen to a hundred or more, are 

 extremely pleasing, and sustain our interest even 

 long after they have become familiar to us. One 

 is apt, at first sight of a flock, especially if it be 

 unexpected, to mistake them for white birds flying 

 by, till they are seen to alight in the water. The 

 length of the bound is enormous, if it be indeed 

 effected by a single impulse; but this point seems 

 hardly to be satisfactorily settled even yet. I feel 

 persuaded that I have more than once seen them 

 deviate from the uniform curve which they usually 

 describe, rising and sinking alternately so as to 

 keep at the same distance from the undulations of 

 the surface ; and Humboldt, one of the most accu- 

 rate of observers, speaks unhesitatingly of their flap- 

 ping the air with their long fins. Indeed, it would 

 else seem almost impossible to imagine that so small 

 a fish, not so large as a herring, should be able to 

 propel itself to the height of twenty feet, and to the 

 distance of more than six hundred, through the air. 

 Generally, one takes his leap first, then the whole 

 flock follow at once, shooting in nearly a straight 

 line, and skimming along a little above the surface; 

 so little that they often strike the side of a rising 

 wave, and go under water. 



