TYPHOONS' (Chinese tei-fun. i.e. "hot wind;" the word, it need scarcely be said, has no connoeti.m with the Typhon of mythology) are violent storms which blow on the coast of Tonquin and China as far n. as Ningpo and the s.e. coasts of Japan. Varenius, in his Geographic Naturalis, describes them as "storms which rage with such intensity and fury that those who have never seen them can form no conception of them; you would say that heaven and earth wished to return to their original chaos." They occur from May to November; but it is during the months of July, August, and September that they are most frequent. They resemble the storms of western Europe (see SToults) in their general characteristics, with this difference, that the main features are more strongly marked. There is a depression of the barometer, over a space more or less etrcular in form, accompanying the typhoon, but it is generally more contracted in area, and deeper and more abrupt than in European storms. It is not uncommon for the barometer, at the center of the depression, to read 28.3 in., and on rarer occasions to fall even as low as 27 in.; and the changes of pressure are very rapid, frequently .2 or .3 in. in an hour. It is this enormous difference of atmospheric pressure between neighboring places, and the consequent rapidity of the fluctuation, which give to these storms their terribly destructive energy—the law regulating the strength of the wind being, that it is proportioned to the difference of pressure between the place from which it comes and the place toward which it blows. The low pressure in the center is confined to a very limited space, and since all around this space the pressure is greater, it follows that the level of the sea there will be higher. Hence, a high wave is frequently found to accom pany these storms, advancing inland, carrying with it ruin and dismay, and not 'Infre quently bearing ships far over the level fields, where they are left stranded a considerable distance from the sea.
Typhoons have their origin in the ocean to the east of China, especially about Formo sa, Luzon, and the islands immediately to the south. They thence proceed, in four cases -out of five, from e.u.e. toward more rarely from e.s.e. to w.n.w., and scarcely ever from n. to s. or from s. to n. ; in other words, their course is generally along the coast of China. The body of the storm advances at the rate of 12 in. an hour and upward, within which the winds blow often from 80 to 100 m. an hour, whirling round the center of atmospheric depression in a direction contrary to the motion of the hands of a watch, as all storms in the northern hemisphere do. They thus rotate in the direction s., e., u., w.; and travel along the coast, so that the coast feels the northern side of the storm, while at it distance front the coast the southern side is alone experienced. The s.w. monsoons (q.v.) prevail in summer over southern Asia, to the eastward of which are the n.p. trade-winds. See WrxDs. Here, then, are two great attrial currents contiguously, but in opposite directions, each highly charged with moisture, especially the s.w. current, which they have taken up from the oceans they have iraversed. It is highly probable that the typhoons take their origin from thew opposing currents, as whirlpools do at the meeting of two sea-currents; and their intensity is aggravated by the large vautity of heat disengaged in the conden sation of thn vapor of the atmosphere into the deluges of rain which fall during the storm —10 and 12 inches of rain frequently falling in one day. Much yet remains to he done toward the examination and explanation of this remarkable class of storms, the first and essential step being the establishing of meteorological stations on the Chinese coast, in Japan, in Forino2a, and in Luzon.