TEMPER4TUEES. 



235 



of Yucatan and the Windw»i-d Passage. Nothing but actual 

 observation has developed the fact that in the Straits of Bernini 

 this current extends across the whole width of the straits and 

 to the very bottom.^ In the Windward Passage the dredgings 



Tlistantes frmrv the Cow^t in- SauticaZ JlfiZes ■ 



2XVI svn juviiL xsix xsK yssi ixsi szm 



Fig. 163.— Off St. Simon's Island, Ga. 



Positinn. 



made on the dividing ridge and on each side of it indicate, from 

 the presence of a large amount of pteropod silt on the southern 



1 Henry Mitchell looks upon the Nich- 

 olas and Santaren Channels, as well as 

 the Providence and Exuma, not as chan- 

 nels proper worn by currents, but as por- 

 tions of the ocean bed left undisturbed in 

 the upheaval of the Bahamas. These 

 thannels are motionless masses of water. 



in which the decline of temperature with 

 the depth is a little more rapid than in 

 the track of the Gulf Stream. MitcheU 

 also considers that the current of the Gulf 

 Stream has had no share in cutting out 

 the Straits of Florida. 



