NATURAL PHILOSOPHY. 217 



time, then an accumulative action is going on, or the beach is increasing. 

 This rule, however, must be received with caution, for it has been remarked 

 that shingle generally accumulates with off-shore winds, and is scoured off 

 during on-shore winds, and we believe that, however acute and scientific 

 observations may be conducted upon the action of the sea at particular locali- 

 ties, it would not be prudent to receive such conclusions as applicable to 

 beaches hi general There was an instance of this last winter, when a heavy 

 ground-swell, brought on by a gale of five hours' duration, scoured away, in 

 fourteen hours, three million nine hundred thousand tons of pebbles from the 

 coast near Dover, England. But in three days, without any shift of wind, 

 upwards of three million tons were thrown back again. It should be men- 

 tioned that these figures are, to a certain extent, conjectural, but they 

 approximate to the truth ; the quantities having been derived from careful 

 measurement of the profile of the beach. 



OX THE GKEAT OCEAX CURRENT OF THE PACIFIC. 



Lieut. Bent*of the U. S. Navy, recently read a paper before the Geogra- 

 phical and Statistical Society of New York, of which the following is an 

 abstract, upon the great ocean current of the Pacific, corresponding with the 

 Gulf Stream of the Atlantic. The Japanese have known it for many years, 

 and call it the Kurosino or Black stream, from its dark blue color compared 

 with that of the adjacent ocean : 



The fountain from which this stream springs is the great equatorial current 

 of the Pacific, which in magnitude is in proportion to the vast extent of that 

 ocean, when compared with the Atlantic. 



Extending from the tropic of Cancer, on the north, to Capricorn, in all 

 probability, on the south, it has a width of nearly three thousand miles. 

 With a velocity of from twenty to sixty miles per day, it sweeps to the west- 

 ward in uninterrupted grandeur around three-eighths of the circumference of 

 the globe, until diverted by the continent of Asia, and split into innumerable 

 streams by the Polynesian Islands, it spreads the genial influence of its warmth 

 over regions of the earth, some of which, now teeming in prolific abundance, 

 would otherwise be but barren wastes. 



One of the most remarkable of these offshoots is the Kuro-Siwo, or Japan 

 Stream, which, separated from the parent country by the Bashee Islands and 

 south end of Formosa, in lat. 22 north, long. 122 east, is deflected to the 

 northward along the east coast of Formosa, where its strength and character 

 are as decidedly marked as those of the Gulf Stream on the coast of Florida. 

 This northwardly course continues to the parallel of 26 north, when it bears 

 off to the northward and eastward, washing the whole southeast coast of 

 Japan as far as the Straits of Sangar, and increasing in strength as it 

 advances, until reaching the chain of islands to the southward of the Gulf of 

 Yedo, where its maximum velocity, as shown by our observations, is 80 miles 

 per day. 



Its average strength from the south end of Formosa to the Straits of San- 

 gar is found to be from 35 to 40 miles per twenty-four hours at all seasons 

 that we traversed it. 



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