24 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 60 



AN OBSERVATION ON THE INTERMINGLING OF RIVER AND 

 OCEAN WATER 



It has long- been known that the water from a shallow river upon 

 entering the sea spreads out fan-like over the surface of the salt 

 water for a very considerable distance with little intermingling. 

 While dredging one day in Suruga Gulf we had striking optical 

 evidence of the truth of this. Though the day was clear there had 

 been during the preceding night heavy rains over the land and the 

 rivers were all swollen and very muddy. It happened that one of 

 the localities in which we wished to work was within the area cov- 

 ered by the extremely muddy water from a small river. The water 

 was so muddy that small objects disappeared from view at a depth 

 of a few inches. On hauling up the trawl a dark hole of clear black 

 water was made through the muddy surface layer, which was then 

 seen to be but a few feet in thickness. 



COMPARISON OF OUR FIGURES WITH THOSE PREVIOUSLY 



PUBLISHED 



As far as southern Kamchatka our figures agree very well with those 

 of " Vega," " Vitiaz," " Variag " and " Predpriatie " for the same 

 region. From this point our course was through territory for which 

 there are no previous records, though the " Vitiaz " established a line 

 of observations somewhat further to the eastward. We found the 

 specific gravity of the water in the Kuril chain higher than would be 

 expected, reaching a maximum in the middle of the group ; these com- 

 paratively high figures undoubtedly represent a purely local condition, 

 the result, as explained by Makaroff, of the upthrust of the abyssal 

 water of the Okhotsk Sea (or of the Pacific, or of both) to the 

 surface. 



About Yezo our figures again agree with those previously pub- 

 lished. There are no records for the west coast of Nipon, and here 

 our observations seem to indicate a belt of water of comparatively 

 low salinity near the coast, probably a very thin and superficial layer 

 resulting from the drainage from the land, intervening between the 

 heavy water of the eastern part of the Sea of Japan and the shore 

 line. 



In the region of the Korean Straits and off the Korean coast our 

 figures do not quite agree with those of Makaroff, though, generally 

 speaking there is but little difference; our figures for southern and 

 eastern Japan more nearly coincide with his. 



