Prudent men will chuse as pure, as warm, and as dry an air as they can; for such an one, by giving strength to the fibres, is salubrious to the lungs, and promotes the circulation. A frigid and dry air is supportable: a moist air is highly pernicious, as by it all the disorders of studious men are aggravated; for it increases laxity, stops perspiration, and occasions catarrhs, pains, and palsies. Every man of learning has it not in his power to repair to Baya or Alexandria, nor does it suit them all to breathe the country air, which is the purest; for there are more that compile than think. The country is not a proper place to pursue such studies; but any man may chuse a healthy habitation in town, and live in a lightsome house, a high apartment, refreshed by a breeze in summer, and enlightened by the sun in winter. He should take particular care to have fresh air let into his chamber every day; without this precaution he lives upon the infected: it should be cooled in summer, and not kept too warm in winter; for the learned, like all weak men, as was the case of AUGUSTUS, are ill able to bear excess of heat or cold: too great a heat relaxes the nerves, but intense cold causes convulsions. In the dog-days we become unfit for labour, as also in the severe cold of winter; and the more tender the constitution, the less it is able to withstand the weather. Such was that of MILTON, whose nerves were relaxed to such a degree in the heat of summer, that he[49] was almost reduced to a state of imbecillity. But the air should be warmed in winter, a fire being kindled for the purpose; for this fresh air succeeds the corrupt air that goes off; nor do exhalations remain, nor does the head grow warm, nor do the feet become cold, which is of great consequence. Cold in the feet hurts the weak by causing pains in the head, the throat, and the breast; it disorders digestion, causes dreadful colicks, obstructs perspiration, and prevents sleep to a very great degree. I have often cured men of note, who had long been without sleep, though they had recourse to the most efficacious remedies, by advising them to warm the soles of their feet at a fire, every night before they went to bed, till the sense of heat became painful. Others have been greatly relieved by a gently stimulating plaster applied to the soles of their feet, and left on both night and day.