600 Mr. J. Y. Buchanan on Chemical Work 



Tongatabu, and the Fiji Islands, back to the Australian coast at its 

 northernmost point, Cape York. The mean specific gravity of the 

 western part of the sea between Australia and New Zealand was 

 1-02647, and that of the eastern part 1*02622, while in Cook's Strait 

 itself it was only 1*02593. Between New Zealand and the Kermadecs 

 the average specific gravity was 1*02630, and between the Kermadec 

 Islands and Tongatabu it was 102651 ; round the Fijis it was 1*02661 ; 

 and between the Fijis and Cape York a very uniform specific gravity 

 was maintained, the mean being 1*02643. We thus see that in the 

 western part of the Southern Pacific the specific gravity of the surface- 

 water is very uniform, varying but little with latitude, showing a very 

 marked difference from the Atlantic Ocean, a difference which was 

 observed to obtain in all parts of the Pacific. 



From Cape York to Hong Kong the course lay through the remarkable 

 series of so-called enclosed seas. The mean surface specific gravities in 

 these seas were as follows : — In and around Torres Straits, 1*02655 ; in 

 the Arafura Sea, 1*02549 ; in the Banda Sea, 1*02603; in the Molucca 

 Passage, 1*02517; in the Celebes Sea, 1*02562; in the Sulu Sea, 1*02496; 

 in the sea enclosed by the Philippine Islands, 1*02532 ; and in the China 

 Sea, 1*02518. On the way to Hong Kong we traversed the Sulu and 

 China seas just at the time when the south-west monsoon had ceased 

 and the north-east one began to blow. When we returned by the same 

 route as far as the south point of Mindanao, the north-east monsoon had 

 already persisted for more than two months ; and the effect of the com- 

 parative dryness of this wind is very evident in the surface specific 

 gravities. The following average values were found : — In the China Sea, 

 1*02534; in the Philippine Sea, 1*02532; and in the Sulu Sea, 1*02570. 

 On the other hand, the few observations made in the northern part of the 

 Celebes Sea showed a diminution of specific gravity, the average being 

 1*02496. Outside the south point of Mindanao a strong and steady 

 north-easterly wind was met with, and for the next ten degrees in longi- 

 tude the mean specific gravity was 1*02596. On nearing the coast of 

 New G-uinea the specific gravity went down rapidly, averaging for a few 

 days before our arrival at Humboldt Bay 1*02519. That a very large 

 river must here empty itself into the sea was evident from the amount 

 of drift-wood with which the sea was covered, and from the superficial 

 distribution of the light water. The specific gravity of water at 50 

 fathoms below the surface was almost perfectly uniform, varying from 

 1*02611 to 1*02636 during the whole cruise from Mindanao to Admiralty 

 Island. When about twenty miles off Humboldt Bay the specific gravity 

 of the water fell as low as 1*02420. Between Humboldt Bay and the 

 Admiralty Island the surface specific gravity was very uniform, varying 

 from 1*02583 to 1*02600, except in one position (lat. 2° 30' S., long. 

 144° 7' E.), where it fell to 1*02554'; but a series of observations on 

 waters taken from different depths at this position showed at once the 



