256 THE PHYSICAL GEOGRAPHY OF THE SEA. 
glisli, we shall have a grand total, perhaps, of not less than six or 
eight thousand, of all sizes and flags, engaged in this one pursuit. 
Of all the industrial pursuits of the sea, however, the whale fish- 
ery is the most valuable. Wherefore, in treating of the physical 
geography of the sea, a map for the whales would be useful. 
555. The sperm whale is a warm-water fish. The right whale 
dehghtS'in cold w^ater. An immense number of log-books of 
whalers have been discussed at the National Observatory, with the 
view of detecting the parts of the ocean in which the whales are 
to be found at the different seasons of the year. Charts showing 
the result have been pubhshed ; they form a part of the series of 
Maury's Wind and Current Charts. 
556. In the course of these investigations, the discovery was 
made that the torrid zone is to the right whale as a sea of fire, 
through which he can not pass ; that the right whale of the north- 
ern hemisphere and that of the southern are two different ani- 
mals ; and that the sperm whale has never been known to double 
the Cape of Good Hope — he doubles Cape Horn. 
557. With these remarks, and the explanations given on Plate 
IX., the parts of the ocean to which the right whale most resorts, 
and the parts in which the sperm are found, may be seen at a 
l^lance. 
