76 



HYDROGRAPHY. 



readily accounts for the difference in the length of passage from 

 Sydney to Van Diemen's Land and back. By keeping off from the 

 coast a sufficient distance, the return passage will be much shortened, 

 or, if in a small vessel, by hugging the coast, the eddy current may be 

 taken advantage of during the fine season. 



FROM SYDNEY TO BAY OF ISLANDS, NEW ZEALAND. 



Between the 19th and 30th of March, 1840. 



Sydney and the north point of New Zealand lie very nearly in the 

 same latitude ; the course is therefore nearly due east. We enjoyed 

 tine weather, smooth seas, and fair winds, and made the run in eleven 

 days. The winds prevailed from the north, and northward and west- 

 ward. On approaching the island, the wind was from the south- 

 west, and after getting to the eastward of Cape Otou, variable. The 

 currents during the passage were from the northwest, until approach- 

 ing New Zealand, when they came from the southeast. After the 

 month of March, on the coast of New Holland, the winds prevail 

 from the southeast, when it is difficult to get an offing. The Peacock, 

 in the month of April, experienced light southeast winds for 12 days 

 after she left Sydney, on her passage to the Friendly Islands ; at the 

 same time was set by a strong current to the northwest, which carried 

 her within 150 miles of New Caledonia before she could make east' 

 ing. Her passage to Tongataboo was in consequence greatly retarded, 

 having been 32 days making the distance of 1700 miles. I think 

 it would be preferable if, on leaving Sydney, the wind should be 

 encountered from the eastward, to stand to the southward until suffi- 

 ciently out of the influence of the coast, or if the wind did not permit 

 that tack to be taken, then beat directly to windward until 100 or 

 150 miles from the port, rather than pursue the northern route. 



FROM BAY OF ISLANDS, NEW ZEALAND, TO TONGATABOO, FRIENDLY ISLANDS. 



Between the 6th and 24th of April, 1840. 



This passage was made by the Vincennes, Porpoise, and Flying- 

 Fish, in 18 days. On the 13th, passed over the Rosetta Shoal. Not 

 finding it, have erased it from the charts. On the 8th day we sighted 



