High Noon on the High Seas 207 



Whales start off by having much less nitrogen in their lungs than do 

 land animals. When they dive, almost all the gas is forced out of the 

 lungs by the increasing water pressure; all that is left is held in the 

 corpuscles of the blood. This reduces the amount of nitrogen that 

 can be released into the blood stream. At the same time, it has been 

 found that whales do a much better job of oxygenating their blood 

 when they do come up for air, renewing ninety per cent of it as op- 

 posed to some twenty per cent in ourselves. Finally, the rate of their 

 heartbeat drops abruptly as soon as they make their dives. These 

 characteristics combined are amply sufficient to overcome the 

 "bends," but even then sperms probably have to return from deep 

 dives in easy stages just like a human diver. 



The sperm whale is in other ways also a sort of supersubmarine. 

 The most characteristic feature of the species is the enormous square 

 head which constitutes almost a third of the entire body. A fifty- 

 eight-foot stranded bull that I once dissected had an eighteen-foot 

 skull. The greater part of this vast head, however, is composed of an 

 enormous fleshy tank. This is covered with straplike muscles run- 

 ning in all directions, and with a thick layer of blubber, like the rest 

 of the animal, but it is hollow and normally filled with up to a ton 

 of light oil. At the bottom is a deep layer of spongy tissue impreg- 

 nated with an exceedingly light viscous wax called spermaceti. It 

 was from this that the animal received its English name, as the early 

 whalers thought this was the animal's supply of the male sperm. This 

 mistaken notion persisted until the present century when more pro- 

 saic but nonetheless remarkable findings of physicists gained general 

 acceptance. These are simply that the whole complex structure is 

 nothing but what is called a hydrostatic organ — a kind of adjustable 

 ballast just like the buoyancy tanks of submarines, or the swim blad- 

 ders of fishes. Exactly how the animal accomplishes the necessary 

 changes in density to make the device work has not as yet — at least 

 to this writer's satisfaction — been explained. 



Quite apart from this tank, the Jhead of the sperm whale is alto- 

 gether unique. First of all, it is completely asymmetrical and this to 

 an extent that surpasses any other backboned animal, certain owls 

 which have one ear pointing forward and the other backward not 

 excluded. If you stand in a sperm whale's skull and look forward, 

 you will see that the bones on one side of the upper jaw are quite 



