Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.
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attained by him, during his voyage of nearly five hundred miles, (British,) was twelve thousand feet above the level of the sea. At the highest point of elevation, it appears from the account that there was less circulation of air than at any point below it. On the earth's surface, then, we have frequent changes of wind, and this more particularly in temperate latitudes, or cli- mates ; and hence there are frequent alterations in the atmos- phere as regards both temperature and electro-magnetism. Semetimes a wind, well known for its peculiarly mild character, assumes so different a nature as to be mistaken for a wind from altogether another quarter of the globe. This arises from va- rious winds supplying one current of air. For instance, we have a south-west wind of some velocity, of a stormy nature, and highly charged with electricity. Suppose, then, this wind to have a parallel breadth of any number of miles, and then to be supplied by north-cast and north-west winds ; of course, under such an influence, we shall have a great reduction of the tem- perature, and other qualities somewhat reversed, for a time, at least. A north-east wind, on the other hand, will frequently have its real nature or character altered, owing to rapid changes of aerial currents during stormy or thundery weather; and this happens more particularly when the observer is situated on the external edge, as it were, of a parallel but contrary current of wind, which varies in diameter, at various seasons, from ten to one hundred miles ; and hence an unusual temperature is given to it. In the centre, however, of the said parallel current you have the true quality unmodified. We now come to the question of health and disease, under the operation of the several winds. The north wind (I here refer to the magnetic north) has a different influence on differ- ent constitutions and ages. The temperature of this wind of course varies, as has been before intimated, according to the seasons ; but its general characteristics are always alike. This wind is usually unattended by hail, or even snow, although if a few points to the eastward it will often be followed, in the whi- ter season, by the above phenomena.