Dr. Forchhamrner on the Constitution of Sea-water. 153 



Of these elements only a few occur in such quantity that their 

 determination has any notable influence on the quantitative analysis 

 of sea-water, viz. Chlorine, Sulphuric acid, Magnesia, Lime, Potash, 

 and Soda. The others, as far as their existence has been determined 

 in the sea- water itself, are found in the residue which remains after 

 evaporation to dryness and redissolution of the salts in water. 



The author next stated that in the water of the ocean far from the 

 shores the principal ingredients always occur very nearly in the same 

 proportions. If we assume chlorine=100, the mean proportion of 

 the other leading constituents is as follows : — 



Mean proportion. Maximum. Minimum. 



Sulphuric acid .. 11-89 12*09 11*65 



Lime 2*96 3-16 2*87 



Magnesia 11-07 11*28 10-95 



All salts 181-1 181-4 180*6 



These proportions apply only to specimens obtained at a long di- 

 stance from shores, or in the open ocean. In the interior of the 

 Baltic, for instance, the proportion of chlorine to sulphuric acid is as 

 100 to 14*97 — to lime as 100 to 7*48 ; and the proportion of chlo- 

 rine to all salts as 100 to 223*0. This constant proportion of the 

 different constituents in the ocean depends evidently not upon any 

 chemical combination and affinity between the different substances, 

 but upon the enormous quantity of salts in the whole ocean, which 

 renders imperceptible any difference that might otherwise arise from 

 the different proportion in which salts are carried into the sea by 

 rivers. It depends, besides, on the uniform action of the numberless 

 organic beings inhabiting the ocean which abstract sulphuric acid, 

 lime, potash, and magnesia from the water, and render them inso- 

 luble. 



The mean quantity of solid matter in the water of the ocean gene- 

 rally, the author found to be 34*304 per 1000. To determine this 

 mean quantity he has divided the ocean into regions, viz. : — 



1st Region. Atlantic, from the Equator to 30° N. lat. ; mean 

 36*169. 



2nd Region. Atlantic, from 30° N. lat. to a line from the north 

 of Scotland to the north of Newfoundland ; mean 35*9/6. 



3rd Region. From the northern boundary of region 2 to the south 

 coast of Greenland ; mean 35*556.. 



4th Region. t)avis's Strait and Baffin's Bay; mean 33*167. 



5th Region. Atlantic, between and 30° S. lat. ; mean 36*472. 



6th Region. Atlantic, between 30° S. lat. and a line from the 

 southernmost point of Africa to the southernmost point of America ; 

 mean 35-038. 



7th Region. Between Africa and the East Indian Islands ; mean 

 33-868. 



8th Region. Between the East Indian and the Aleutic Islands ; 

 mean 33*506. 



9th Region. Between the Aleutic and the Society Islands ; mean 

 35*219. 



