CURRENTS OF THE SEA. I39 



we have additional evidence touching this China Stream, as to 

 , which (^ 263) but little, at best, is known. 



266. The Cold Asiatic Current. — Inshore of, but counter to 

 the China current, along the eastern shores of Asia, is found 

 (^ 257) a streak, or layer, or current of cold water answering to 

 that between the Gulf Stream and the American coast. This 

 current, like its fellow in the Atlantic, is not strong enough at all 

 times sensibly to affect the course of navigation ; but, like that in 

 the Atlantic, it is the nursery (§ Go) of most valuable fisheries. 

 The fisheries of Japan are quite as extensive as those of New- 

 foundland, and the people of each country are indebted for their 

 valuable supphes of excellent fish to the cold waters which the 

 currents of the sea bring down to their shores. 



267. Humboldt's Current. — The currents of the Pacific are 

 but little understood. Among those about which most is thought 

 to be known is the Humboldt Current of Peru, which the great 

 and good man whose name it bears was the first to discover. It 

 has been traced on Plate IX. according to the best information 

 — defective at best — upon the subject. This current is felt as far 

 as the equator. (See Appendix D.) 



268. I have, I believe, discovered the existence of a warm cur- 

 rent in the inter-tropical regions of the Pacific, midway between 

 the American coast and the shore-lines of Australia. 



269. This region affords an immense surface for evaporation. 

 No rivers empty into it ; the annual fall of rain, except in the 

 " Equatorial Doldrums," is small, and the evaporation is all that 

 both the northeast and the southeast trade-winds can take up and 

 carry off. I have marked on Plate IX. the direction of the sup- 

 posed warm w^ater current which conducts these overheated and 

 briny waters from the tropics in mid ocean to the extra-tropical 

 regions where precipitation is in excess. Here being cooled, and 

 agitated, and mixed up with waters that are less salt, these over- 

 heated and over-salted waters from the tropics may be replenish- 

 ed and restored to their rounds in the wonderful system of oceanic 

 circulation. 



270. There are also about the equator in this ocean some curi- 

 ous currents which I do not understand, and as to which obser- 

 vations are not sufficient yet to afford the proper explanation or 

 description. There are many of them, some of which, at times, 



