X. 
TEMPERATURES OF THE CARIBBEAN, GULF OF MEXICO, AND 
WESTERN ATLANTIC. 
Havine given the reader a general sketch of the configu- 
ration of the sea-bottom in the districts traversed by the 
* Blake," we may now pass to an examination of the tempera- 
tures and currents of the sheet of water covering that region. 
(Fig. 140.) The temperature sections of the Gulf of Mexico 
were obtained mainly by Lieutenant-Commander Sigsbee ; those 
of the Caribbean and along the Gulf Stream, with the exception 
of the few observations made by the “ Albatross,” were taken 
by Commander J. R. Bartlett on the * Blake." They are here 
reproduced as they have been kindly sent to me by Professor 
J. E. Hilgard, Superintendent of the Coast Survey.' 
Of course, during the cruises, sound- 
ings were taken with Sigsbee's modifica- 
е 1 Tn addition to ће graphie method of representing 
each temperature section which has been adopted on 
wy many of the maps of this volume, it has been found 
ё | convenient to construct curves (Fig. 141), showing at a 
е | glance the temperature at апу depth. Ву su- 
sg a perposition the eurves of separate observations 
may be readily compared ; in the same way, 
Mi we may, by means of eurves, bring 
n to the eye at onee the thermal 
conditions of such distant points 
4g as we wish to contrast. In at- 
0" p^ El tempting thus to set forth the 
i^ p = oa a рен temperature of currents, we 
Ue жеты эше RE Y A ae M should not forget that at every 
A -3 moment they are changing in di- 
Fig. 141. — Temperaturo Sections. (Curves.) rection and intensity, much as are 
the -a£mospherie currents ; and 
their graphical representation merely gives us their most general features, leaving 
the local disturbances to be more or less accurately defined. 
