But greater precaution is necessary for the valetudinary; amongst whom are the greatest number of those that live in cities, and almost all that are fond of study: that care may rectify the disorders which arise from their constitution, situation, or study. Any of these then, who has concocted well, will rise in the morning safely; he that finds the concoction not completed, ought to lie still; and if he be under a necessity of rising, to go to sleep afterwards. He that has not concocted at all, should be entirely at rest, and neither venture upon labour, nor exercise, nor business. He that is troubled with crude belching, without pain of the præcordia, ought now and then to drink cold water, and withal to confine himself to certain rules; to live in a house well lighted, that enjoys the summer’s breeze and the winter’s sun; to avoid the meridian sun, the morning and evening cold, as also the air of rivers and lakes; and by no means to expose himself to the sun breaking out in a cloudy sky, lest he be sometimes affected with heat, and sometimes with cold, which very often occasions gravedoes(18) and catarrhs. These inconveniences are to be guarded against with greater diligence in sickly places, in which they even cause a pestilence. We may know a body to be in health, when every day in the morning the urine is first white, and then of a light red colour: the first shows that the concoction is going on, and the other, that it is compleated. When any person awakes, he ought to wait a little, and then, unless it be the winter time, to wash his mouth plentifully with cold water; in long days, to take the air in the middle of the day, before meat; or, if he cannot do that conveniently, after it. In winter especially, to rest the whole night; but, if he is obliged to study in the night, to do it not immediately after eating, but after concoction. He, that in the day-time has been employed either in domestic or civil business, ought to set apart some time for the refreshment of his body; the principal part of which is exercise, which ought always to go before meat: in one that has laboured little(19), and has concocted well, it should be stronger; in one who has been fatigued, and has not concocted well, it may be more gentle. Proper exercises are, reading aloud, handling of arms, the ball, running, and walking; which last is better not upon plain ground: for an ascent and descent agitates the body with some variety, unless it be very weak. And it is better in the open air, than in a portico; better in the sun, if the head can bear it, than in a shade; better in a shade formed by walls, or parks, than under a roof; a straight walk is better than a winding. In most cases a beginning sweat should put an end to exercise, or at least lassitude, that does not amount to fatigue; and that sometimes in a less, sometimes in a greater degree. In all these exercises, there should neither be, as among wrestlers, an inviolable rule, nor too violent labour.