Upon several Accounts, this may be esteem’d the best and Noblest of all _Exercises_ for a Sick Person; whether we consider it with Respect to the Body or the Mind; if we Enquire after what manner it affects the Body, we shall find that it is a kind of mixt Exercise, partly _Active_ and partly _Passive_; the lower parts of the Body, being in some measure employ’d, while the upper parts are almost wholly Remiss or Relax’d; nay, where a Man is easie, is sure of his Horse, and rides loose, there is very little Action on his Part, but he may give himself to be as careless almost as if he were Seated on a Moving Chair; so that he may be said to be Exercis’d rather than to Exercise himself; which makes the Case widely different from almost all other sorts of Exercise, as Walking, Running, Stooping, or the like; all which require some Labour, and consequently more Strength for their Performance; in all which, the Muscular Parts must be put to some Stress, and some of the Secretory Vessels made to throw off too much, while others throw off too little; whereas in Riding, the Parts being incomparably more relax’d, there is a better Disposition towards an equal Secretion of the Morbisick Particles, and a less Expence of the Animal Spirits, the chief Agents in all regular Secretions; so that a Sick Person may by this means be greatly reliev’d and not tir’d, whereas by other more violent ones, it is possible he may be tir’d and not reliev’d. As for the Parts which are more immediately acted upon by this Exercise; it is very plain they are the whole Contents of the Lower Belly, so that the Glands of the _Mesentery_ and the Intestines, so frequently accus’d of Obstructions, may in a special manner be clear’d, and their Tone recovered by such repeated Agitation; which is a thing so manifest and allow’d, that it would be needless to multiply Words in the explaining of it. But there is another sort of Assistance communicated to the Intestines, which is not so much heeded, and that is the great Alteration, which is made by this Agitation, in some of the Morbifick Particles, as they come to be squeez’d out of their several Glands into the Intestines, which in the time of Riding is doubtless in a much greater quantity than at other times. These Particles must not be suppos’d to be barely carryed off as Excrementitious, but to undergo a Change in their Texture, to be several times in a manner Cohobated, from Acid and Acrimonious, to be Volatiliz’d, and in some measure render’d inflammable; that there is some such Alteration made in the more liquid part of the Contents of the Intestines, before they come to grow hard in a true State of Health is easie to prove, and I believe agreed on by most Enquirers into the Oeconomy of Nature, and that there is some Defect in these Operations of the Bowels, in some sick People, is evident from the Consistence, Smell, and other Qualities of these Contents, different