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out of the Yellow Sea during these months and parts of it may get mixed with the warm water of the Kuro-siwo.
The branch of the Japan stream which flows through the Straits of Corea during the summer months discharges a warm current into the Japan Sea, frequently at a velocity of from two to three miles an hour. This current then runs along the west coast of Japan as far as the north of Yezo. Its breadth, however, gradually decreases and its velocity proportionately decreases till arriving at the parallel of about 38° N. latitude, after which it can scarcely be detected. When nearing the Straits of Tsugar and La Perouse, however, the current is again perceptible, and in the centre of these channels, it, at all times, sets to the eastward, its strength depending greatly upon the local winds.
On the westward side of the Japan Sea but few observations have ever been taken: a south-west set has, however, been experienced, and this, I think, may very probably be expected during the winter and early part of the spring.
It has been stated above that the Kuro-siwo flows into the Japan Sea through the Corean Straits, during summer or the continuauce of the S. W. monsoon only, but that there is a constant outset through the Straits of Tsugar and La Perouse. It is therefore evident that there must be some other cause than the current of the Japan stream to account for the eastward set through these straits during the winter months. And I think there will be little difficulty in discovering the reasons for this when we consider, that at the same time that the N. E. monsoon commences in the China Sea, and prevents the Kuro-siwo from flowing into the Corean Straits, north-west winds set in the Sea of Japan, blowing almost constantly and with considerable force. These heap (so to speak) the waters up before them until they find an outlet through the straits. The origins of both the Gulf and the Japan Streams are due to causes of a similar nature and the same results are observable on our own shores. A gale of several days’ duration from the north-
