126 



MArtlOX EXPEHITION TO DAVIS STRAIT AXD BAFFIN BAY 



at a distance of 1,000 feet, and 270 feet per day (0.002 knot per lioiu) 

 at a distance of 100 feet from the bero;. Such a cnrrent is of such a 

 comparatively small magnitude that it is masked completely by the 

 passing surface movements due to the waves or the Avinds. As proof 

 of the above, Ricketts points to the drift of growlers that even on 

 days of light airs and breezes is away from the parent Ijerg. 



I 



The Melting of ice 



Figure 84. — Fresh ice melting in salt water, according to laboratory 

 experiments. sets up a movement of water near the ice in much the 

 same position shown in the bottom sketch. The upper two draw- 

 ings show the di.-stribution of temperature and salinitj- after a few 

 moments of melting. (Sketches from I'ettersson and Sandstrom, 

 1915.) 



With conclusions so contradictory it is evident that the picture is 

 far from clear. The experiments of Pettersson. Sandstrom, and 

 Aitken are all oi)cn to the criticism that the laboratory conditions 

 may not simulate those existing at sea. Barnes's conclusions are weak- 

 ened by the fact tliat neither Taylor or Thuras obtained similar re- 

 sults, though Thuras did not have sufficiently sensitive instruments.' 





