84 



FRIDTJOF NANSEN. 



M.-N. Kl. 



The mean difference between tlie hours of the transits (and the me- 

 dium hours between them) of the moon across the Greenwich meridian and 

 the hours of high-water (and low-water) at Stat. 41, according to our current- 

 measurements, is thus 9 hours and 48 minutes. 



The current-measurements at Stats. 19 and 20, on August 4th and 5th, 

 are on the whole not so complete as to allow of a determination of the 

 hours of high- and low-water. The only observations that may seem to 

 give informations of some value in this respect were taken about 4 p. m. 

 (3 p. m. Greenwich time) on August 5th, when there was a distinct mini- 

 mum of movement, all layers being apparently at rest, and this should 

 indicate high-water. The transit of the moon across the Greenwich meridian 

 occurred at 4.59 a. m. (Greenwich time) and the difference will be 10 

 hours and i minute, which agrees fairly well with our above-mentioned 

 result. 



According to Mr. RoUin Harris's studies on "Arctic Tides" [191 1] the 

 mean semidiurnal tidal hour for Port Virgo, on the north-western coast 

 of Spitsbergen (79° 43' N. Lat., 10" 44' E. Long) is XII. 56 lunar hours, or 

 just 13 solar hours. ^ 



This is abuot 3 hours and 12 minutes longer than our observations 

 gave for our stations in the sea only some 40 naut. miles, or 80 kilometres, 

 to the north of Port Virgo. It has to be considered that Harris's tidal hour 

 is referred to the occurrence of mean high water, and "is generally about 

 twenty minutes less, than the tidal hour at full and change" of the moon. 

 On the other hand our observations on August 17th to 19th were taken 



^ For Mosel Bay, farther east on the north coast of Spitsbergen (79'' 53' N. Lat., 16^ 

 E. Long.) it was about L4, or about 13 solar hours and 52 minutes. 



