Besides, it must not be neglected to enjoyn the wounded Person to be let Blood both before and after the Operation, if he hath a Fever or a Plethory; and more especially it is to be remember'd to cause his Body to be kept open at least every other Day, with Clysters, obliging him to keep a good Diet, and to avoid all violent Agitations both of Body and Mind, abstaining from eating Flesh till the Fourteenth Day. All manner of Venery and Conjugal Embraces, which prove fatal at this time, are to be prohibited during forty Days, to be counted from the Day of the Operation; as they are also in all other considerable Wounds. * * * * * {197} CHAP. IV. _Of the _Caries_ or Ulcer of the Bones, _Exostosis_, and _Nodus_._ _What is_ Caries? It is the Putrifaction of the Substance of the Bone, or else its Ulcer or Gangrene. _Whence doth the _Caries_ of the Bone derive its Original?_ It proceeds from an internal and external Cause; the former being that which hath been produc'd at first in the Substance of the Bone; and the other that which takes its Rise from an inveterate Ulcer in the Flesh, which hath communicated its Malignity to the Substance of the Bone, and by that means corrupted it. _How is the _Caries_ known which proceeds from an inward Cause?_ By the continual and violent Pains which are felt before, and continue for a long time without diminution; as also afterward by the alteration of the Flesh that covers the Bone, and which becomes soft, spongy, and livid. _By what means is a _Caries_ that derives its Origine from an outward Cause, discover'd?_ By the quality of the purulent Matter that issueth out of the Ulcer in the Flesh, which is blackish, Unctuous, and extremely stinking; as also by the help of the Probe, that discovereth {198} asperity or roughness in the Bone when it is laid bare. _What Means are to be us'd in order to cure a _Caries_ proceeding from an external Cause?_ The Powder of Flower-de-luce may be us'd, and it is sufficient for that purpose, when the _Caries_ is superficial; but it is necessary to take _Oleum Guyaci_, and to soak Bolsters therein, to be laid upon the Ulcer when it is deep; or else _Aqua-Vitæ_ or Brandy, in which have been infus'd the Roots of Flower-de-luce, Cinnamon, and Cloves. Lastly, the actual Cautery, which is Fire, must be apply'd thereto. _What is to be done when the _Caries_ proceeds from an internal Cause?_ The Flesh must be open'd to give Passage to the _Sanies_ that runs out of the ulcerated Bone, to the end that Exfoliation may be procur'd; and if the Ulcer hath not as yet laid open the Bone on the outside, the Trepan ought to be apply'd; but the Ulcer or _Caries_ must be afterward handled, as we have even now declar'd. _What is _Exostosis_?_ It is the Swelling of a Bone made by the settling of a corrupt Humour in its proper Substance. _What is _Nodus_?_