12 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 60 



current of small salinity which comes from the Inland Sea, entering 

 the Sea of Japan by the Straits of Shimonoseki. This heavy water 

 in flowing northward along the coasts of Nipon, Yezo and Sakhalin 

 very gradually becomes less and less saline. 



Near the Siberian coast, water with a specific gravity of from 

 1.0250 to 1.0255 descends from north to south, washing the whole 

 coast of the western part of the Sea of Japan and making itself felt 

 even in the Korean Strait. 



The specific gravity of the water in the Sea of Japan is higher than 

 that in corresponding latitudes in the Pacific ; in going from Hako- 

 date to Vladivostok the specific gravity diminishes rapidly west of 

 134 and near Vladivostok is about 0.0011 less than in the Strait of 

 Tsugaru. 



The mean specific gravity of the water of the Sea of Japan, both 

 at the surface and in the deeper portions, is 1.0260. 



Tracing a line from the Bay of St. Olga to the middle of the 

 Korean Strait we find that in the western part the specific gravity, 

 both at the surface and below, does not pass 1.0260. The heavy 

 water which enters the Strait of Korea occupies in width more than 

 half the strait, and its entire depth ; further northward, however, the 

 thickness of the heavy layer does not exceed 100 meters. Water 

 with a specific gravity of more than 1.0262 is only found in the 

 eastern part of the sea. 



The Strait of La Perouse includes two zones of water of different 

 salinities and temperatures. In the southern part there is a warm 

 current which descends toward the east near the coast of Yezo, and 

 in the northern part, near the coast of Sakhalin, there is a cold current 

 running toward the westward out of the Sea of Okhotsk. The line 

 of separation between these two currents is not vertical but strongly 

 inclined ; the water from the Sea of Okhotsk, lighter and colder, 

 advances in a mass having a cuneiform section over the wanner, 

 but also heavier, water of the eastern part of the Sea of Japan which 

 passes downward and, turning to the right on account of the rota- 

 tion of the earth, extends far toward the northeast under the cold 

 water. This water from the Sea of Jar*in has a specific gravity of 

 I.0260, and a temperature of io/C. in August; it is probable that in 

 winter the temperature does not fall below 3 C. 



The surface water of Aniva Bay, in southern Sakhalin, has a 

 specific gravity of 1.0245; for a while in August its temperature 

 may be as much as \J° C, but the rest of the year it is much lower. 



