BLUE WHALE. 253 



there arc two sorts of dives: the series of shallower or surface dives followed by the deep dive 

 when (he whale 'sounds' or goes down for a longer period. The Blue Whale after coining to 

 the surface from a deep dive makes about twelve to fifteen of the shallow dives, then goes down 

 again for an interval of from five to ten minutes or more. Millais has timed them at these 

 longer dives, from ten to twenty minutes down. At each of the short dives the vertex of the 

 head first appears and simultaneously the spout is delivered (Plate 13, fig. 3) ; the open nostrils 

 I lien take in breath and close with the sinking of the head, which passes forward beneath the 

 surface. Then a section of the broad back arches from the water and slides forward and under 

 in its course, till finally the dorsal fin appears, small and low, and as it too revolves, wheel-like, 

 the animal sinks beneath the waves. At about three times its own length (some 150 to 200 

 feet) it again comes to the surface, 'blows' and goes down again, until having sufficiently 

 refreshed its lungs, it plunges into the depths, often throwing its great tail or flukes out of water 

 at the end of the movement. Scoresby says (1820, vol. 1, p. 481) that it "very rarely throws 

 its tail in the air" when it descends. My own observations are limited but seem to bear this 

 out to some extent. Millais observed that "only occasionally, when actually 'on feed' does 

 it ever exhibit the tail clear of the water," but in making its big dive, a bull "will often raise 

 the tail clear of the water." The duration of the shallow dives is about 12 to 15 seconds. 



The height of the spout varies according to conditions whether the whale has been down 

 long or if a wind be blowing to distort the shape of the column, which is comparatively high 

 and expanded slightly at the summit. The Newfoundland whalemen did not pretend to dis- 

 tinguish the spout of the Blue Whale from that of the Common Finback, though some writers 

 have stated that the greater size of the Blue Whale's spout is characteristic. A very successful 

 photograph of the Blue Whale in the act of spouting I succeeded in obtaining from the deck 

 of the Puma in Placentia Bay, Newfoundland (Plate 13, fig. 3). It shows the lateral lips of 

 the blowholes well raised as the breath is forcibly expelled, and the conical shape of the vapor- 

 ous column, slightly distorted by the wind. The height of the column probably does not 

 exceed twenty feet, though estimates run as high as fifty. In Newfoundland waters I had a 

 chance to photograph the spout of a Blue Whale at a moment when the Norwegian captain 

 of the whaler's crew stood up to lance the whale. The comparative height of the column in 

 the photograph (see Amer. Naturalist, 1904, p. 620) is about two and one-third times that of 

 the man, or about fourteen feet. Rawitz estimates about a meter (3 feet). The whale in 

 diving leaves a long 'slick' or smooth elliptical area on the surface, caused by the counter 

 currents of water that rush in to fill the potential vacuum as the whale rises and descends. 



The speed of a Blue Whale when travelling at a normal rate is in the vicinity of ten to 

 twelve knots an hour, but when frightened it is undoubtedly much more. Two whales which 

 we pursued in the whaling steamer Puma in Placentia Bay, Newfoundland, could not be over- 

 hauled after a long chase, though the little vessel was making all of ten knots an hour. We 

 finally had to abandon the pursuit as the pair disappeared in the distance rising and spouting 



