257 



its anchors on the moving bottom of the sea (called rade marec) 

 and runs ashore.^ 



Besides the motion of the sea, there is one circumstance more 

 worthy of notice, as bearing upon the organic life of this sea- 

 shore. It is the chemical composition of the sea-water. The sea- 

 water contains, at this distance (about eighteen degrees) from the 

 equator, the greatest amount of salt in solution ; more than the 

 water near New England, and a good deal more than the sea 

 immediately under the equator. This remarkable fact has been 

 shown by Linz, a German scientific traveller, on his voyage 

 round the world.^ The rivers of the northern shore of Hayti 

 are not large enough to exert an extensive influence upon the 

 composition of the sea-water, even in the immediate neighborhood 

 of their mouths, and, moreover, they are generally barred up by 

 sand-banks during a great part of the dry season. These sand- 

 bars prevent again a large pouring in of sea-water into the 

 river, and thus the river water is quite fresh and sweet in the 

 immediate neighborhood of the sea, so much so that vessels take 

 in their drinking water there. But notwithstanding this, (and 

 it is an interesting physiological fact,) I found relatively more 

 sea-fishes going up annually from the sea into these rivers, than 

 ascend the German rivers ; showing how flexible their nature 

 must be to bear the sudden change in the saltness and density 

 of the water, when passing from that deeply saline ocean into 

 fresh water. The case is different with those sea-fishes of New 

 England and Germany which enter rivers ; they have always to 

 pass through brackish water, and thus the change is effected 



gradually. 



(To be continued.) 



Dr. C. T. Jackson said that he had found in analyses 

 of sea-water from coral regions a greater amount of car- 

 bonate of lime than is found in water from other parts of 

 the ocean. He supposed it to be derived from the decom- 



1 In the harbor of Jeremie, which is uot protected against this north wind, two 

 vessels ran ashore at one time during one of the last winters. This occurs nearly 

 every year. 



2 See Humboldt's Kosmos, I. p. 320, where we find also the reason for this re- 

 markable phenomenon. 



PROCEEDINGS B. S. N. H. — VOL. VI. 17 NOVEMBER, 1857. 



