From Sydney to Cook Strait. 97 



9°.3 C, remained almost stationary between 150 fathoms and 

 400 fathoms, descending from 8°. 8 C. to 8°. 2 C. at the latter 

 depth, whence it decreased more rapidly to 5° C. at 600 fathoms, 

 to 3 C. at 800 fathoms, to 2 C. at 1 100 fathoms, and to o°.8 C. 

 at the bottom in 2150 fathoms. Similar conditions of tempera- 

 ture were observed at Station 160, nearer to the Australian 

 coast, where, however, the warm stratum, still commencing with 

 8°. 8 C. at 150 fathoms, ended with 8°. 2 C. in 300 fathoms, 

 while 5 . 1 C. were registered at 500 fathoms, 2°.\ C. at 800 

 fathoms, and o°.2 C. at the bottom in 2600 fathoms. It seems, 

 therefore, that at the latter station the ship had already crossed 

 the axis of this warm under-current. 



The distance run between Station 158 and Station 159, and 

 between the latter station and 'Station 160, was about 350 miles, 

 so that this current cannot be less than 400 miles broad. The 

 distance between Station 160 and Cape Northumberland, the 

 nearest point on the south coast of Australia, is about 380 

 nautical miles, and the axis of the current may be laid down on 

 the chart at a distance of about 500 miles from the Australian 

 coast, bending round in a south-easterly direction towards the 

 wide space of open water at the foot of Victoria Land, discovered 

 by Sir James Ross. It may be taken for granted that the 

 South Australian current just described, as well as the currents 

 to the westward of the Crozet Islands and Kerguelen Land, 

 represent the outflow of the warm water of the Indian Ocean 

 through the Southern Ocean into the Antarctic Basin. 



Section from Sydney to Cook Strait, New Zealand, and 

 from Cook Strait to Tonga Tabu (Plate 14, Table VIII.). — 

 Narrow as the sea between Australia and New Zealand seems 

 when compared with its great neighbour the Pacific, its average 

 width is a thousand miles, and a ship sailing at the rate of 150 

 miles a-day will consume a week in accomplishing the voyage from 

 Sydney to Wellington. Divided from the basin of the Pacific 



