152 EKMAN. ON DEAD-WATER. [norw. pol. exp. no. «]. 



lighter. The hoat dragged hy a force, in each case greater than in the pre- 

 ceeding. In Fig. 4 very little is wanting to free it from the dead-water. 

 (Pp. 62 seq.). 



PI. XVI. 



Photographs from the side, of the larger _FVa?»-model in a 5 cm. thick 

 fresh-water layer; Experiments 77, 80, 81, 84, p. 80. Salt-water black; fresh- 

 water lighter. (Pp. 62 seq.). 



Figs. 1 — 3: in dead-water, with a towing-force, increased in successive ex- 

 periments. 

 Fig. 4: at a high speed, without dead-water. 



PI. XVII. 



Photographs from the side, of the larger .Fram-model in a 7 cm. thick 

 fresh-water layer; Experiments 103, 105, 106, 108, pp. 80 — 81. Salt-water 

 black; fresh-water lighter. (Pp. 62 seq.). 



Figs. 1 — 3: in dead-water. 



Fig. 4: at a high speed, without dead-water. 



