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 strong and the active. Hence the propriety of a more generous diet, and an extra glass of wine during the prevalence of an epidemic, especially cholera.

11. MALARIA.—It is a generally received opinion that the greater proportion of the diseases of India is the consequence of malaria generated in the decomposition of animal or vegetable matter: that a certain ethereal essence, whether a gas or a vapour, a film or an aroma, is evolved by such substances, when exposed to putrefaction in moist high temperatures, which has the property of causing fever when inhaled, or absorbed externally. The germs of disease are so ethereal, that they have hitherto baffled all art and all science to identify them, either in air, earth, or water. We can separate the component parts of all three, and bottle them up like May-dew; we can handle electricity, galvanism, and magnetism as we would material agents; we can divide the light of day into its constituent elements, and convert the red, and the yellow, ray into peculiar uses,—and the violet ray into a photographic pencil, far surpassing in truth, the paintings of the most able artists. But who can analyze a cubic foot of air, and be able to ascertain whether it be good or wholesome, or contain the essence of small-pox or cholera, or plague, or intermittent fever? Yet our belief is that these must exist as distinct