VEGA-EXPEDITIONENS V ET EN S KA P LIG A ARBETEN. -^OS 



To begin with, it can be proved, that the freezing of sea- 

 water involves a total revolution of its cliemical constitution. 

 Chemical analysis shows, that the quantitative proportion of 

 the constituents Ca, Mg, Na, Ka, Cl, H'2S04 is other in ice 

 than in sea water. 



It was believed fonnerly that the composition of the water 

 did change from one part of the ocean to another, until For- 

 chammer, by application of exact analytical methods, showed, 

 that the chemical constitution of sea-water is nearly the same 

 över the whole earth. The relation of the chemical compo- 

 nents of the salt of the ocean is according to Forchammer 

 (if the amount of Chlorine is assumed = 100) 



Cl CaO MgO SO3 Total araourt of salt. 



100 2.93 11.03 11.88 181.1 



Tliese numbers are on the whole confirmed by recent investi- 

 gations. Only with regard to the proportions of MgO and SO3 

 differences have been fouud, whicli are however so slight, 

 that the hydrographers are uncertain, whether to attribute 

 them to a real unsteadiness in the composition of sea-water 

 or to inevitable analytical errors. I will return to this remark- 

 able circumstance låter. 



Those, who support the common theory, that sea-ice is in 

 itself wholly destitute of salt and only mechanically encloses 

 a certain quantity of unfrozen and concentrated sea-water, 

 must confess, that we in this case ought to find by chemical 

 analysis exactly the same proportion between Cl, MgO, CaO, 

 S0;5 etc. . . in the ice and in the brine as in the sea-water itself. 



In order to decide the question, I requested Mr. Fors- 

 berg, the assistant teacher of analytic chemistry of the labora- 

 tory, to undertake a complete quantitative analysis of the fol- 

 lowing six water-samples. j\g 1 — 4 I chose out of the collec- 

 tions of the Vega, so as to represent the constitution of the 

 Siberian sea-water at different clepths and of difFerent specific 

 gravity. J\'o 5 & 6 are saraples of unfrozen brine collected by 

 the Vega-explorers on the surface of the ice during cold 

 winter days. I feel bound on this occasion to express my 

 sincere gratitude to Mr. Forsberg for bis skilful assistance. 

 The particulars of the analyses, the methods etc. will be 

 treated in next paper, wliich is specially devoted to the hydro- 

 graphy of the Siberian sea. The numbers of this table repre- 

 sent the proportions of the constituents if chlorine is = 100 



