88 



FRIDTJOF NANSEN. 



M.-N. Kl. 



has probably an average depth of more than 1500 metres, at least, the 

 tidal wave may be expected to travel with a velocity of more than 240 

 miles an hour. As was mentioned above, it is possible that the ice-pressures 

 reach their maximum, or cease, some time after high-water, in which case 

 our value of the difference between the transit of the moon and high-water 

 will be too high. Whether the correction thus needed, would be sufficient 

 to make up for the above discrepancy seems, however, doubtful. The above 

 value (i4 h n m ) of the tidal hour would agree better with the time of 

 high- water of Port Virgo (tidal hour = i3 h ) and Mosel Bay (tidal hour = 

 i3 h 5o m ) on the north coast of Spitsbergen. 



The sea where these observations were made in June 1896, was 3200 

 metres deep. It is interesting to note that regular heavy ice-pressures are 

 caused by the tidal currents over such a deep sea. And there were many 

 more such regular pressures, occurring twice (or sometimes only once) in 

 24 hours, than are mentioned above. This fact seems to indicate that the 

 tidal wave was greater in this region than it is generally assumed that it 

 should be over the deep Ocean. 



During October, November, and December, 1893, when we were over 

 the continental shelf north of Siberia, or near its edge, ice-pressures occur- 

 red in the days about every spring-tide, as a rule very regularly twice 

 in 24 hours. I find the following observations in my diary. For the sake 

 of convenience I give the notes in their original form with local time, but 

 have then transformed the hours of the transit of the moon across the 1 

 Greenwich meridian to this local time as well. 



