1198 



THE CETACEANS 



there is some variation in this respect according to age. " When emerging to the 

 surface," writes Captain Scammon, " the first portion of the animal seen is the re- 

 gion of the hump, then it raises its head and respires slowly for the space of about 

 three seconds, sending forth diagonal!} 7 a volume of whitish vapor, like an escape of 

 steam; this may be seen from the masthead at a distance of three to five miles. In 





THE SPERM WHALE. 

 (One-one-hundred and twenty-fifth natural size.) 



respiring at its leisure, the animal sometimes makes no headway through the water; 

 at other times it moves quietly along at the rate of two or three miles an hour, or, 

 ' if making a passage ' from one feeding ground to another, it may accelerate its ve- 

 locity. When in progressive motion, hardly an instant is required for inspiration; 

 when the animal dips its head a little and momentarily disappears, then it rises 



