There are two kinds of abstinence. One, when the patient takes no food at all: the other, when he takes only what is proper. The beginnings of diseases call for fasting and thirst: after that in the distempers themselves moderation is required, so that nothing but what is proper be taken, and not too much of that; for it is not fit after fasting, to enter immediately upon a full diet. And if this be hurtful even to sound bodies, that have been under the necessity of wanting food for some time, how much more is it so to a weak, not to say a diseased one? And there is nothing which more relieves an indisposed person, than a seasonable abstinence. Intemperate men amongst us chuse for themselves the seasons of eating, and leave the quantity of their food to the physicians. Others again compliment the physicians with the times, but reserve the quantity to their own determination. Those fancy themselves to behave very genteelly, who leave every thing else to the judgment of the physicians, but insist upon the liberty of chusing the kind of their food; as if the question was, what the physician has a right to do, not what may be salutary to the patient; who is greatly hurt as often as he transgresses either in the time, measure, or quality of his food. CHAP. XVII. OF SWEATING. A sweat is procured in two ways; either by a dry heat, or a bath. A dry heat is raised by hot sand, the laconicum, and clibanum(28), and some natural sweating places, where a hot vapour exhaling out of the earth is inclosed by a building, as there is at Baiæ amongst the myrtle groves. Besides these, it is solicited by the sun and exercise. These kinds are useful, wherever an internal humour offends, and is to be dissipated. Also some diseases of the nerves are best cured by this method. And the others may be proper for weak people: the heat of the sun and exercise agree only with the more robust; when they are falling into a disorder, or even during the time of distempers not violent, provided they be free of a fever. But care must be taken, that none of these be attempted either in a fever(29), or in the time of crudity.