OF TIDES. 337 



ters as at the full and change of the moon *. It is evident, 

 from a table of these tides for twenty-six days, that there was 

 but one tide a day ; and this, during the whole time, was at its 

 mean height between eleven and one. These tides, therefore, can 

 have no relation to the phases of the moon. 



Let us now take a cursory view of the effects produced by the 

 tides in the northern part of the South Sea. At the entrance of 

 Nootka it is high water, on the days of new and full moon, at 

 twenty minutes past twelve : the perpendicular rise and fall eight 

 feet nine inches ; which is to be understood of the day tides, and 

 those which happen two or three days after the full and change. 

 The night tides rise nearly two feet higher f. These semidiurnal 

 tides differ from ours in taking place at the same hour, and exhibit, 

 ing no sensible rise till the second or third day after the full moon; 

 all which is perfectly inexplicable on the lunar hopothesis. 



These northern tides of the South Sea, remarked in April, be. 

 come, in higher latitudes, stronger in May, and still stronger in 

 June; which cannot be referred to the moon's course then passing 

 into the southern hemisphere, but must be ascribed to the sun's 

 course passing into the northern hemisphere, and proceeding, as its 

 heat increases, to fuse the ices of the north pole : besides, the di. 

 rection of these northern tides towards the line constitutes a com- 

 plete confirmation that they derive their origin from the pole. 



At the entrance of Cook's River there was a strong tide setting 

 out of the inlet at the rate of three or four knots an hour : higher 

 up in the inlet, at a place four leagues broad, the tide ran with pro. 

 digious violence at the rate of five knots an hour. Here the mark* 

 of a river displayed themselves, the water proving considerably 

 freshert. 



What Cook calls a river, is nothing but a real northern sluice, 

 through which the polar effusions are discharged into the ocean. 

 Mid.dleton$ found between lat. 65 and 66, a considerable inlet 

 running west, which he calls Wager's River ; and, after repeated 

 trials of the tides for three weeks, found the flood constantly coining 

 from the east. This is another of the northern slucies. 



* Cook, Dec. 1777. i Cook, April 1778. J Cook, May 1778. 



; Voyage to Hudson's Bay, 1741 and 1742. 



VOL. III. z 



