APPENDIX I 341 



The harmonic constants for these places will be 

 given in a paper on Arctic Tides about to be issued 

 by the Coast and Geodetic Survey. 



As indicated by its name, a "lunitidal interval" is 

 the time elapsing between the passage of the moon 

 across the meridian of the place or station and the 

 occurrence of high or low water. If two stations have 

 the same longitude, then the difference between the 

 lunitidal intervals for the two stations denotes the 

 difference in the times of occurrence of the tides. If 

 they have not the same longitude, then the intervals 

 must be converted into lunar hours (1 lunar hour = 

 1.035 solar hours) and increased by the west longitude 

 of the stations expressed in hours. The result will be 

 the tidal hours of the stations expressed in Green- 

 wich lunar time. The difference between the tidal 

 hours for two stations will be the difference in the 

 time of occurrence of the tides expressed in lunar 

 hours. 



One of the most important results brought out from 

 the tidal observations of the expedition is the fact that 

 high water occurs two hours earlier (in absolute time) 

 at Cape Columbia than at Cape Sheridan. The Cape 

 Columbia tides are even earlier than the tides along the 

 northern coast of the Spitzbergen Islands. These facts 

 prove that the tide at Cape Columbia comes from the 

 west. It is the Baffin Bay tide transmitted, first, north- 

 westerly through the eastern portion of the Arctic 

 Archipelago to the Arctic Ocean, and then easterly 

 along the northern coast of Grant Land to Cape 

 Columbia. That the tide wave should be felt after 

 a passage of this kind, instead of practically disap- 



