IX.] 



SUPER-COOLED MIST. 



341 



lor the navigator, which we experienced during the following 

 days, when the tackling of the Vcya was covered with pieces of 

 ice so large, and layers so thick, that accidents might have 

 happened by the falling of the ice on the deck.^ 



ALGA FKOM IRKAIPJJ. 



Laminaria soUdungula (J. G. Ag.), 



The dredgings here yielded to Dr. Kjellman some algse, and 

 to Dr. Stuxberg masses of a species of cumacea, Diastylis 



^ A more dangerous kind of icing down threatens the navigator in severe 

 weatlier not only in the Polar Seas but also in the Baltic and the North Sea. 

 For it happens at that season that the sea-water at the surface is over- 

 cooled, that is, cooled below the freezing-point without being frozen. 

 Every wave which strikes the vessel is then converted by the concussion 

 into ice-sludge, which increases and freezes together to hard ice so speedily 

 that all attempts to remove it from the deck are in vain. In a few hours 

 the vessel may be changed into an unmanageable floating block of ice 

 Avhich the sailors, exhausted by hard labour, must in despair abandon to its 

 fate. Such an icing down, tliough witli a fortunate issue, befell the steamer 

 Sofia in the month of October off Bear Island, during the Swedish Polar 

 Expedition pf I808. 



