SEA 



^. That the mean spec. grav. of sea water near the equator is 1.02777 j 

 intermediate between that of the N. and S. hemispheres. 



3. That there is no notable difference in sea waters under different 

 meridians. 



4. That there is no satisfactory evidence that the sea at great depths 

 is more salt than at the surface. 



5. That the sea in general contains more salt where it is deepest, and 

 most remote from land, and that its saltness is always diminished in the 

 vicinity of large masses of ice. 



6. That small inland seas, though communicating with the ocean, are 

 much less salt than the open ocean. 



7. But that the Mediterranean contains rather larger proportions of 

 salt than the ocean. 



SEA WATER, saline contents of. 



Sea water contains in solution, muriate of soda, sulphate of soda, mu- 

 riate of lime, and muriate of magnesia j Dr Wollaston has also ascer- 

 tained that it contains potash, though in a proportion less than r^^th 



part of sea water at its average density. The following analysis of sea 

 water, brought from the middle of the North Atlantic, as given by Dr 

 Marcet, may serve as a specimen. The quantity operated upon was 500 

 grains : 



Muriate of soda ~~~~v~~ ~~ 13,3 grs. 



Sulphate of soda 2,33 



Muriate of lime ~~~~~~. 0,975 



Muriate of magnesia -~~~*~<*^*. 4,955 

 '21,460 



Analysis of the water of the Dead Sea, by Dr Marcet ; the quantity 

 operated upon being 100 grains. 



Muriate of lime ,^~^~~~w~~~~~ 3,920 grs. 

 Muriate of magnesia w ~~ ww , 10,240 

 Muriate of soda ~~~~v~~~~~~~~~ 10,360 



Sulphate of lime ~~~~~ , 0,054 



24,530 



SEA WATER, temperature of. 



In Baffin's Bay, the Mediterranean Sea, and the Tropic.il Seas, the 

 temperature of the sea diminishes with the depth, according to the ob- 

 260 



