No. 16.1 EXPLANATION OF THE DEAD-WATER PHENOMENON. 113 



should be very sharp, nor is the vessel's shape of any material importance. 

 It would therefore be expected, that dead-water occurs at about all places 

 where a considerable quantity of fresh-water Hows out over the sea. 



The answers obtained in reply to an appeal published in foreign 

 newspapers (see p. 8) do not seem to agree with this conclusion. On the 

 contrary, it seems to follow from the replies that dead-water is very little 

 known except in Scandinavia ; and only in Norway is it of common occurrence. 

 Only a few cases of dead-water in other parts of the world e. g. in the 

 Mediterranean, the Congo River (see the Supplement), and off the Fraser 

 and Orinocco Rivers — have come to my notice. In addition, dead-water is, by 

 Norwegian seamen, said to occur on the Gulf of Mexico and off the St. 

 Lawrence and the great rivers of South America; and on the French rivers 

 Loire and Garonne, phenomena are known which possibly are due to 

 dead-water 1 . (See further Chapter I.) 



To completely clear up this apparent contradiction, I neither have a sufficiently 

 complete and reliable knowledge of the actual distribution of the phenomenon, 

 nor am I well enough acquainted with the hydrographic conditions of the 

 coasts, and especially of the river-mouths, in different parts of the world. I 

 will therefore, only try to show here, how the above mentioned facts may 

 probably be explained. 



There are three circumstances which must be considered, namely : the 

 conditions of formation of the water-layers, the kind of vessels navigating the 

 place concerned, and the seamen's attention to the phenomenon. 



The formation of considerable fresh-water layers by rain-fall, may be 

 regarded as exceptional, and the melting of ice does not come into account 

 in this connection, outside the polar regions; the occurrence of dead-water, 

 must consequently be as a rule, restricted to places where rivers fall into the 



It may be pointed out that in the case of Accounts No. 32 and 39—42, it cannot be 

 decided whether dead-water has been the cause of the accident, or not. They have 

 been inserted each on its own merits, because no other accounts from the particular 

 neighbourhoods concerned, were available. It is hardly necessary to point out that 

 the fact mentioned in No. 45 p. 32, might for instance just as well have been caused 

 by sludgy ice or some other circumstance resisting the vessels, as by reason of a 

 case of dead-water. On the other hand, it seems very likely that the cases under No. 43 

 and Account Nr. 44 refer to cases of dead-water — in the last two of these cases the 

 vessel had lost her headway almost entirely, and alter a while (when after having 

 stopped rowing, they began again?) she regained her speed. 



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