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surrounding atmosphere, which, in its turn, performs the same duty, and soon a large portion of the atmosphere becomes involved in the same vorticular action. An extensive condensation of vapor going on in the centre, the air becomes lighter there than elsewhere in the revolving disc, and forms a kind of chimney for the denser air below to pass up through; and when this process has been going on for some time the air beneath is sufficiently exhausted to admit of the storm disc descending to the surface of the earth, after reaching which, it takes up a progressive motion and is impelled by magnetic attraction towards the magnetic poles.
A seeming contradiction to this statement may be found in the “Argyleshire’s” Typhoon, which I have here represented as travelling W. by S., and in a direction nearly parallel to the Magnetic Equator; but when it is remembered that some portions of the earth are heavily charged with magnetism (as is shown by the variation of the mariner’s compass to the extent of two points or more of deviation from the true Meridian, and especially in the Danish Sound and Baltic Sea, where the local magnetic forces in the adjoining countries—especially Sweden, where iron is found in great quantities—is so great as to attract the compass very much more) it may be quite possible that similar attractions exist in China, or on the island of Hainam which is called by the Chinese “the Mother of Typhoons.”
I am aware, while supporting Col. Reid’s theory of magnetism in typhoons, that opinions and theories have been published in opposition to it; but none have proved it to be wrong, or have accounted more clearly for the progressive motion of circular gales; and as all theories as yet made known with regard to the origin and cause of circular gales are but speculative in their character, I see no reason why the theory of magnetism in connection with typhoons should not receive a fair share of consideration, and as far as I am personally concerned, I give it the preference.
Some writers are of opinion that there is a close con-
