628 SAND-MOVEMENT ON THB NEW SOUTH WALES COAST, 



gales from the north-east quadrant are to those from the south- 

 east quadrant at Clarence River as 1 : 6, and at Sydney as 1 : 1 1 J. 



These figures will perhaps correct the general impression tbat 

 the north-easters are more prevalent on the north coast than in 

 Sydney or on the south coast, and also that the southerly winds 

 and gales do not reach our northern ports with the same frequency 

 as at Sydney. 



After about 30 years' experience on this coast, I am of opinion 

 that the monsoonal north-east wind extends with undiminished 

 force at least as far south as Jervis Bay. About this point it is 

 pushed upwards by the colder south-west wind from the Antarctic, 

 and is also deflected to the east in the direction of the south- 

 eastern current before referred to. At Twofold Bay the north- 

 easters do not begin to be felt before the end of October or 

 November, and cease about February; whereas on the Richmond 

 River the same winds begin in September and do not cease till 

 March or early April. 



The south-west, south, and south-east winds extend well up 

 into Queensland, though the "Southerly Burster" does not often 

 get beyond Port Macquarie.* 



The above table will show that the south-westers blew for the 

 greatest number of hours during two years of the period 1894- 

 1903; while the north-easters prevailed during the remaining 

 eight years. 



Tidal Current. — The current due to the tide on the New South 

 Wales littoral may be said to be negligible. The direction of the 

 tidal wave is almost at right angles to the coast, and the times 

 of high water of any one tide at Point Danger and Twofold Bay 

 are almost identical. This means that the tidal current is so 

 weak that it is controlled entirely by a very light breeze, and 

 this cannot, in itself, have any influence on the velocity of sand- 

 movement. The rise and fall of the water has, however/ a large 



* Hunt, H. A., " An Essay on Southerly Bursters," Journ. Proc. Boy. Soc. 

 N. S. Wales, 1894, xxviii., p. 155. 



