AGASSIZ: BAHAMAS. 77 



Grand, Double Breasted, Stranger, Carter, Fish, Pensacola, and the 

 Hog Cays are, in the order named, the westernmost of the long line 

 extending from Walker Cay Channel on the northern edge of the bank 

 alonrf its eastern edije as far as Cheroki Sound near the southeastern 

 extremity of the bank. This line of cays protects the eastern face of 

 Little Abaco and of Abaco from the action of the heavy trade wind 

 swell which pounds upon the eastern face of the cays ; they will iu 

 time disappear completely, as the intervening channels become wider, 

 thus exposing their western face to the long reach of the sea, which 

 has already removed nearly all traces of the former line of outer cays, 

 islets, and sheltered cays which must once have formed the continu- 

 ous Little Bahama Bank, — then a bank on which were many islands, 

 and which was fringed on its sea face by cays of which no trace is now 

 left except the shallower patches on the banks to indicate their former 

 existence. The outer line of cays is flanked on the sea side by the 

 narrow flat of the bank between them and the 18 or 20 fathom line, 

 where the bank drops suddenly to a hundred or a hundred and twenty 

 fathoms. On this flat coral reefs flourish, as more or less extended 

 patches of heads or clusters of heads, in a depth of four to six fiithoms. 

 Inside of this line the corals do not flourish well, being too much ex- 

 posed to the full force of the Atlantic swell. This belt of corals we 

 crossed twice, on going off" the bank at Green Turtle Cay, and again on 

 attempting to enter Little Harbor. 



The inner shore line of the outer row of cays is generally formed by 

 low vertical cliff's, behind which rise the rounded summit lines of the 

 cays, scarcely reaching at any point a greater height than fifty feet. 

 All these islands are of peolian origin, the rocks composing them differ- 

 ing in no wise from those of the other parts of the Bahamas. The char- 

 acter of the bottom, however, changes somewhat after we approach the 

 Barracouta Rocks. There it begins to be somewhat more marly, and 

 soon after going eastward we enter a district the bottom of which is 

 characterized on the charts as marly ; finally, when we get off" Green 

 Turtle Cay, we find that the marl closely resembles the peculiar white 

 ooze covering so great a part of the bank to the westward of Andros. 

 This white marl fills the channel all the way from Little Abaco to 

 Man-of-War Channel. The samples of the bottom taken off" West End 

 Rock of Little Abaco, in three fathoms of water, are fine marl of a 

 light gray color, and of a consistency almost like plaster of Paris, but 

 of a V)luish tint. Off" the eastern face of the outer cays the bottom is 

 covered by the coarse sand formed of coral debris and of seolian rock, 



