Page:Physical Geography of the Sea and its Meteorology.djvu/170

144 sun rises. The time at which it becomes calm after the land and sea breezes is indefinite, and the calms are of unequal duration. Generally, those which precede the sea breeze are rather longer than those which precede the land breeze. The temperature of the land, the direction of the coast-line with respect to the prevailing direction of the trade-wind in which the land is situated, the clearness of the atmosphere, the position of the sun, perhaps also that of the moon, the surface over which the sea breeze blows, possibly also the degree of moisture and the electrical state of the air, the heights of the mountains, their extent, and their distance from the coast, all have influence thereon. Local observations in regard to these can afford much light, as well as determine the distance at which the land breeze blows from the coast, and beyond which the regular trade-wind or monsoon continues uninterruptedly to blow. The direction of land and sea winds must also be determined by local observations, for the idea is incorrect that they should always blow perpendicularly to the coast-line. Scarcely has one left the Java Sea—which is, as it were, an inland sea between Sumatra, Borneo, Java, and the archipelago of small islands between both of the last named—than, in the blue waters of the easterly part of the East Indian Archipelago, nature assumes a bolder aspect, more in harmony with the great depth of the ocean. The beauty of the Java Sea, and the delightful phenomena which air and ocean display, have here ceased. The scene becomes more earnest. The coasts of the eastern islands rise boldly out of the water, far in whose depths they have planted their feet. The south-east wind, which blows upon the southern coasts of the chain of islands, is sometimes violent, always strong through the straits which separate them from each other, and this appears to be more and more the case as we go eastward. Here, also, upon the northern coast, we find land breezes, yet the trade-wind often blows so violently that they have not sufficient power to force it beyond the coast. Owing to the obstruction which the chain of islands presents to the south-east trade-wind, it happens that it blows with violence away over the mountains, apparently as the land breeze does upon the north coast; yet this wind, which only rises when it blows hard from the south-east upon the south coast, is easily distinguished from the gentle land breeze. The regularity of