828 



SCIENCE. 



[N. S. Vol. IV. No. 101. 



dress correspondence to the Chairman, at 

 Cosmos Club, Washington, D. C. 



H. Carrington Bolton, Chairman, 



F. W. Clarke, 



A. E. Leeds, 



A. B. Prescott, 



Alfred Tuckerman, 



H. W. Wiley, Committee. 



CURRENT NOTES ON PHYSIOGRAPRY. 

 PACIFIC OCEAN CURRENTS. 



Dr. Casar Puls contributes an elaborate 

 discussion, based on original records, of the 

 surface temperatures and currents in the 

 equatorial belt of the Pacific Ocean to the 

 'Archiv der Deutschen Seewarte' (Ham- 

 burg, XVIII., 1895, 1-38, with 12 monthly 

 charts). The chief interest attaches to the 

 equatorial counter current, which maintains 

 its eastward course all across the ocean be- 

 tween the wind-driven, west-flowing equator- 

 ial currents on the north and south, the lat- 

 ter being much the stronger of these two. 

 The north equatorial current, from 9° to 20° 

 N., is strongest in March ; it is not alto- 

 gether supplied at its east end by the weak 

 southward current along our west coast ; it 

 receives much water from the counter cur- 

 rent which turns northwest at its east end, 

 and not southeast, as ordinarily mapped. At 

 the west end of the north equatorial cur- 

 rent, part turns north to flow past Japan, 

 and a lesser part south to join the counter 

 current. The great south equatorial cur- 

 rent, from 12° S. to 5° IST., is strongest in 

 September, and has its highest velocity 

 along its northern margin, sometimes over 

 100 nautical miles in 24 hours. It is largely 

 supplied by up- welling water along the west 

 coast of South America, where the wind 

 blows off- shore ; the Humboldt surface cur- 

 rent is not sufficient to feed it. Part of 

 this great equatorial current turns south 

 before reaching the Solomon Islands ; the 

 rest passes on north of New Guinea and 

 turns sharply back at the ' root ' of the 



counter current, except from December to 

 May, when this branch is turned back on 

 itself by the northwest monsoon then and 

 there prevalent, forming a short counter cur- 

 rent south of the equator. The north coun- 

 ter current, extending all across the ocean, 

 is said to be much influenced, but not pro- 

 duced, by the winds. Near its west end it 

 is favored for three-quarters of the year by 

 the southwest monsoon ; and from July to 

 October, when it is, as a whole, strongest 

 and broadest, its east half is favored by the 

 narrow belt of monsoon winds there and 

 then occurring. It is narrowed and weak- 

 ened in our winter, when these favoring 

 winds are wanting, and from January 

 to March, under the extended northeast 

 trade, it may be stopped or locally re- 

 versed ; but where and whenever these 

 adverse winds weaken or shift, the current 

 reappears, and sometimes with increased 

 strength. Yet, as a whole, it is regarded 

 as a compensation current, discharging 

 eastward the excess of the wind- driven 

 south equatorial current, which has no suf- 

 ficient escape at its west end. 



If a narrow current, 8,000 miles long, 

 can be a compensation current, a previous 

 note on this subject in Science (III., 1896, 

 921) should be somewhat modified. It 

 may be added that according to these 

 descriptions the Pacific counter current 

 serves indirectly to carry water contin- 

 ually from the southern into the northern 

 hemisphere, receiving a supply from the 

 south at its west end, and discharging its 

 flow chiefly northward at its east end; thus 

 doing what is more directly accomplished in 

 the Atlantic by the cross-equator extension 

 of the south equatorial current past the 

 Guiana coast. In the Pacific, as in the 

 Atlantic, a compensation for this excess of 

 surface movement into the northern hemi- 

 sphere must exist beneath the surface, and 

 with fuller data as to deep temperatures 

 this may aid in deciding the cause of the 



