When the belly is costive, so as to evacuate very sparingly, and from that cause flatulencies, dimness of sight, pains of the head, and other disorders of the superior parts, grow troublesome, then ’tis fit to take a purge: for what assistance can rest or abstinence afford in these disorders, of which they are the principal causes? He that wants to be lax, let him first use such food and wine as produce that effect: and if they don’t succeed, let him take aloes. But purging, though it be sometimes necessary, yet, when it is frequent, becomes dangerous; for thus the body will be habitually deprived of its nourishment, and by that means become valetudinary, for a body in a weak state is the most liable to all kinds of distempers. [Sidenote: _What heats and cools the body._] The body is heated by unction, salt water, and more so if it be warm; all salt provisions, and austere wine. On the contrary, it is cooled by bitter and fleshy substances, taken with an empty stomach; the bath after meals, and sleep, unless it be too long, and all acids; the coldest water; oil, if it be mixed with water; and lotus(26). [Sidenote: _What moistens and dries the body._] The body is rendered humid(27) by less exercise than ordinary, frequent bathing, a full diet, much drink, a walk after it, and continuing awake. Walking long, and briskly, has of itself the same tendency; and morning exercise, if one does not eat presently after it; and those kinds of food, which come from cold climates, or rainy, or otherwise damp. On the contrary, dryness is caused by immoderate exercise, hunger, unction, heat without moisture, immoderate use of salt, cold water, and the taking of food immediately after exercise, and such particularly as comes from dry and hot climates. [Sidenote: _What binds and relaxes the belly._] The belly is bound by labour, sitting still, rubbing potter’s chalk upon the body, and by diminishing the usual quantity of food, as also if it be taken but once a day by one who is accustomed to it twice; by drinking little, and not till one has eat as much, as he designs for the time; rest after meat. On the other hand, the belly is relaxed by an increase of walking and food, motion after meat, and drinking frequently in the time of meals. ’Tis necessary also to know this that a loose belly is bound by a vomit, and a costive one is loosened by the same: and a vomit immediately after meat binds it; but one that comes some time after, renders it lax. [Sidenote: _Of the different ages_.]