while a summer visit to England will be found of great CHAP. advantage after a winter at Madeira.

Finally, it is by the adoption of such changes of residence as, after a careful study of the individual peculiarities of each case, seem likely to improve the general health, to increase nervous tone, and to invigorate digestion and sanguification, that the real advantages obtainable from climates may be made available for phthisical patients. The idea of specific climatic influence as curative of consumption is to be abandoned, all individual peculiarities in each case are to be studied, and, by the indications so gathered, our advice is to be guided.

The conditions influencing nutrition, and especially the purely digestive processes, are to be considered as of primary importance; the localities requisite to ensure open-air exercise, with light and purity of atmosphere, are to be especially recommended. Damp and low situations, and miasmata from animal or vegetable impurity, are to be shunned. A tonic and bracing air is preferable to a relaxing, damp, and warm atmosphere, Extreme ranges of temperature, as likely to cause congestion of the bronchial membrane and of the lung, are to be avoided, but a uniformly high average is not advisable in the residence to be selected. Nor is a persistent sojourn in any one climate or locality to be recommended.

The effects of mere change of air on the pulmonary membrane and on the nervous system are to be remembered; and the patient who has passed one winter in Madeira or Algiers is more likely to benefit by a return to these localities if the intervening summer has been passed in a cool or temperate climate, like England or Switzerland.

It is never to be forgotten that the most hardy, vigorous, and long-lived races in the world, the civilisers who can tolerate the greatest extremes of new

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CHAP. climates, and who have colonised the remotest counXXVIII. tries with the moral, mental, and physical constitution best fitted to work and to endure, come from these islands, and have been nursed in a temperate climate. The races which have decayed or died out, whose mission in the world appears to have been only temporary, and who did not, therefore, possess the elements of long endurance, were inhabitants of the relaxing climates around the Mediterranean or of the far East. The existing differences between the races of the North and South are equally illustrative of the influences which tend to vigour. Let the traveller contrast the inhabitants of Germany, France, or England, with those of Spain, Portugal, or Southern Italy, and the vast difference in energy of character and in accomplished work will be apparent. Or let us take the colonies of these countries, and compare the vitality and vigour of the United States or of Canada with the exhausted energies of the South American Republics.

It may be replied, that the institutions and the religion of these various countries have much to say to their present condition; and this is true. But national character and physical vigour are the primary elements out of which institutions are formed, and which originated their power or their weakness. And with all history before us, including that of the Roman Empire, which, as it became intermixed with the Eastern element, crumbled away before the energy of the North, we cannot avoid the conclusion that climate has, among the many influences apparent, a place among the more important agents which give a stamp to the character and elaborate the vigour of nations.

And to apply this line of thought to the practical questions daily before the physician, we cannot believe that a disease of lowered nutrition, with consequent exhaustion of vital powers, is best treated in all instances

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by a residence in climates of the enervating and relax- CHAP. ing character; while, on the other hand, we have abundant evidence that all which is tonic and invigorating in external influences is productive of corresponding good in the vital system, provided that individual constitutions and requirements are carefully studied.

ABSORPTION of tubercle, 115, Age, in acute diseases originating