142 BOOK OF NATURE LAID OPEN. 



a similarity to those of quadrupeds, that Linneeus has 

 placed it in the same class ; to which its claim, and 

 that of the other cetaceous fishes, seem, indeed, little 

 inferior to that of the Seal, where the last gradation, 

 in that order of animals, may be said to end. 



In its instinctive tenderness, the Whale is, indeed, 

 entitled to our admiration ; but, as we shall have oc- 

 casion to speak more fully on that subject by and 

 by, we will, for.the present, proceed to the consider- 

 ation of the general 



Structure of Fishes. 



In attending to these, we will soon observe that, 

 if the body of a bird is shaped in the most convenient 

 manner for making its way through the air, a no less 

 extraordinary degree of divine wisdom is evident in 

 the conformation of the finny inhabitants of the deep 

 to that element in which they exist. To make these 

 creatures buoyant and flexible, yet firm to oppose 

 Jthe strongest currents, the great Creator has consti- 

 tuted them of very different materials, and of a dif- 

 ferent construction from other animals. To enable 

 them to traverse with ease and swiftness the watery 

 regions, the greater part of them have the same ex- 

 ternal form, sharp at each end, and swelling in the 

 middle. To preserve them from being hurt by the 

 action and temperature of the surrounding fluid, 

 as well as to enable them to glide more smoothly 

 through it, many of these are covered with a coat of 

 scales, others with a fat oily substance, and the whole 



