THE ARCTIC SEAS. ] 33 



proceed more than three hundred horny pLites, set 

 parallel to each other, and very close ; they run 

 perpendicularly downwards, are fringed on the inner 

 edge with hair, and diminish in size from the 

 central plate to the first and last, the central one 

 being about twelve feet long. The plates are com- 

 monly called whalehone, and their substance is well 

 known to everybody ; they form an important object 

 of the fishery. The lower jaw is very deep, like a 

 vast spoon, and receives these depending plates, the 

 use of which is this : when the Whale feeds, he 

 swims rapidly just under or at the surface, with his 

 mouth wide open ; the water with all its contents 

 rushes into the immense cavity, and filters out at the 

 sides between the plates of the whalebone, which are 

 so close, and so finely fringed, that every particle of 

 solid matter is retained. 



Though the AVhale, like all other Mammalia, is 

 formed for breathing air alone, and is therefore ne- 

 cessitated to come to the surface of the sea at certain 

 intervals, yet those intervals are occasionally of great 

 length. We well know that we could not intermit 

 the process of breathing for a single minute without 

 great inconvenience, and the lapse of only a few 

 minutes would be followed by insensibility and perhaps 

 death. The Whale, however, can remain an hour 

 under water, or, in an emergency, even nearly two 

 hours, though it ordinarily comes up to breathe at 

 intervals of eight or ten minutes, except when feeding, 

 when it is sometimes a quarter of an hour, or twenty 

 minutes submeiged. Xow the object of breathing 

 is to renew the vital qualities of the blood by pre- 



