18 EKMAN. ON DEAD-WATER. [norw. POL. EXP. 



the windward side, where the water is rippled by the breeze. The surface of the water 

 between the rip and the ship's side is smooth and unrippled. The steering is now entirely 

 lost, and the ship turns her stem in the direction of the surface current. It feels as if 

 something were fastened to the ship and holding it back. 



"If the wind freshens again, the phenomenon reoccurs in the same manner, but of 

 course, the order is reversed. First, the single rip (Fig. 9) is seen; it moves aft, and when 

 it leaves the stern, the three rips (Fig. 8) are formed. As the speed of the ship increases, 

 these rips draw farther and farther off, and when they are IV2 or 2 ship's lenght from 

 the stern, the ship gets rid of the dead-water. The rips however remain, and as the ship 

 sails away, they disappear in the distance to the great satisfaction of the seamen. 



"That the vessel may get free, a stronger wind than that which prevailed when it 

 got into dead-water, is generally required. A sudden freshening more easily frees the 

 vessel, than a gradual increase of the wind, so that in the latter case a greater increase 

 is necessary than in the former. 



"When empty, my ship less often took dead-water; the breeze then had to be very 

 feeble and even with the least increase of wind she was free again. This, no doubt, de- 

 pends on the smaller draught of the ship. I also observed that vessels of smaller draught 

 were less liable to dead-water; deeper vessels, on the contrary, more so. A good sailer 

 sooner gets free than a worse ship of the same draught. 



"Both when taking dead-water and in getting free, the change seemed to take place 

 suddenly, although, certainly, the influence of the dead-water (or of the current) made itself 

 felt on the steering, even if the ship kept her ordinary speed. 



"In the Sound, by beating against a fresh, northerly breeze, and with the current 

 going strongly northward, the ship took dead-water every time she tacked, and then 

 kept it during some minutes until she got up her speed again. In a more feeble breeze 

 and with the same current, the ship could not go about, whereas, by veering, one could 

 get her round. In some cases, I have also seen vessels incapable of going round either 

 way, beat back again with backed sails and stern ahead. 



"When sailing out of the Baltic, dead-water is not encountered before past Falsterbo, 

 and it then gradually grows stronger until out in the Kattegat. There, it is probably 

 strongest between Lceso and Skagen where it then again diminishes, in some degree, in 

 getting out into the Skagerrack. During feeble easterly winds dead-water can be perceived 

 over the whole Skagerrack, and stretches as far as the westgoing current along the Nor- 

 wegian coast; but farther in the North Sea and off England I never observed it. In the 

 Gulf of Finland I have perceived dead-water in the months of June and July, but very 



feebly. 



"I have observed that dead-water always occurs in connection with more or less of 

 a current and that this has been strongest at the surface, whereas, below, there has been 

 either no motion at all or the current has taken an opposite direction. Probably the light 

 water from the Baltic has moved upon the Salter North Sea water. 



"If sailing out through the Kattegat before a decreasing SW. breeze, the ship, when los- 

 ing her steering, commonly turns her stem towards NE.; and as the current commonly has 

 the same direction, the ship is soon brought into critical proximity to the Swedish coast, 

 and often we have been forced to drop anchor on this account so as not to drift ashore. 

 I cannot say whether the vessels everywhere turn their stems in the direction of the cur- 

 rent, but I have observed it off the Norwegian coast. 



"Several methods have been tried to get rid of the dead-water. Thus I have poured 

 oil before the stem, have had a hawser laid under the bottom of the ship and drawn it 

 from stem aft, have worked the rudder, but everything was of no avail. Twice it has 

 happened in the Kattegat that a steamer has crossed our wake just astern, and curiously 

 enough, the ship both times got free from dead-water, without my perceiving any increase 

 of wind." 



