Chemistry and Physios. 



385 



produces an ochre-red powder, the so-called rhodizonic acid. This 

 the authors find to be identical with their dioxydichinoylben- 

 zene C 6 (OH) 2 4 .— Ber. Berl Chem. Ges., xviii, 1833, July, 1885. 



G. F. B. 



6. Composition of Ocean water. — Me. W. Dittmae has given 

 (Proc. Phil. Soc. Glasgow, vol. xvi, Dec. 3, 1884) a summary of 

 his results obtained in the investigation of the specimens of ocean 

 water brought home by the Challenger expedition. We cite 

 briefly from this abstract. Mr. Dittmar remarks in the outset on 

 the small change in the constitution of the solids in solution in the 

 ocean produced by the contributions of rivers, stating that the 

 estimated annual amount from the thirteen principal rivers of the 

 earth, 1*337 X 10 9 tons (of 1000 kilos each), when compared with 

 the amount in the ocean water of dissolved solids (46,280 billion 

 tons in the 1*3 trillion tons of water), is so small that it would 

 take 30,000 times as much to tell distinctly on the most exact sea- 

 water analysis which could be made by our present methods. 



The water was found to contain an appreciable amount of base 

 over and above that which would neutralize the two principal 

 acids, and this is in the state of carbonate ; and part of this car- 

 bonate must be carbonate of lime. From the mean results of 

 77 analyses, this surplus base per 1,000 grams of ocean water 

 is equivalent to 0*25 grams of carbonate ol lime ; but this number 

 may need a correction, considered beyond. The following table 

 gives the results of Mr. Dittmar's 77 analyses : 



Average composition of Ocean-water Salts. 



Per 100 parts 



of Total Salts. 



Dittmar. 



Chlorine 55-292 



Bromine 0"1884 



Sulphuric acid, SO 3 6"410 



Carbonic acid, C0 2 0'152 



Lime, CaO 1-676 



Magnesia, MgO 6-209 



Potash, K 2 1-332 



Soda, Na 2 0... 41-234 



(Basic oxygen equivalent to 



the halogens) (-12-493) 



V 



Total salts. 



100-000 



Per 100 of Halogen calculated 





as Chlorine. 



Dittmar. 



Forchhammer. 



99-848 



Not determined 



3402 



Not determined 



11-576 



11-88 



0-2742 



Not determined 



3-026 



2-93 



11-212 



11-03 



2-4f>5 



1-93 



74-462 



Not determined. 



.... 



---- 



180-584 



181-1 



Combining acids and bases, we have [Dittmar) — 



Chloride of sodium 77-758 



Chloride of magnesium __ 10'878 



Sulphate of magnesium 4"737 



Sulphate of lime 3-600 



Sulphate of potash 2 - 465 



Bromide of magnesium _ 0-217 



Carbonate of lime 0-345 



Total salts 100-000 



* Equal conjointly to 55-376 parts of chlorine, which accordingly is the per- 

 centage of " halogen reckoned as chlorine " in the real total solids. 



