sorts of Creatures, and different particulars in every sort. And thus, _Madam_, I have delivered unto you my opinion concerning the cure of Fevers by Blood-letting: Which I submit to the correction of your better judgment, and rest, Madam, _Your faithful Friend_ _and Servant._ [1] In his Treatise of Fevers, _c._ 4. XXXIV. _MADAM,_ Your _Author_ is not onely against Phlebotomy or Blood-letting, but against all Purging Medicines, which he condemns to _carry a hidden poyson in them, and to be a cruel and stupid invention._ But certainly he shall not have my assent; for if they be Poyson, they are a very beneficial Poyson; and Physical Purgations, in my opinion, are very necessary and profitable for the prolonging of life, and taking away of diseases, provided they be proper for those diseases in which they are used; and so is Phlebotomy, Vomits, and the like: but Medicines are often wrong applyed, and many times the disease is so various, that it is as hard for a Physician to hit right with several Medicines, as for a Gunner or Shooter to kill with Powder and small Shot a Bird flying in the Air; not that it is not possible to be done, but it is not ordinary, or frequent: neither doth the fault onely lie in the Gun, Powder, or Shot, but in the swiftness of the flight of the Bird, or in the various motion of the air, or in a hidden wind, or mist, or the like; for the same Gunner may perhaps easily kill a Bird sitting in a bush, or hopping upon the ground. The like may be said of Diseases, Physicians, and Medicines; for some diseases have such hidden alterations, by the sudden changes of motions, that a wise Physician will not, nor cannot venture to apply so many several medicines so suddenly as the alteration requires; and shall therefore Physicians be condemned? and not onely condemned for what cannot be helped by reason of the variety of irregular motions, but what cannot be helped in Nature? For some diseases are so deadly, as no art can cure them, when as otherwise Physicians with good and proper medicines, have, and do as yet rescue more people from death, then the Laws do from ruine. Nay, I have known many that have been great enemies to Physick, die in the flower of their age, when as others which used themselves to Physick, have lived a very long time. But you may say, Country-people and Labourers, take little or no Physick, and yet grow most commonly old, whereas on the contrary, Great and rich Persons take much Physick, and do not live so long as the common sort of men doth. I answer: It is to be observed, first, that there are more Commons, then Nobles, or Great and rich persons; and there is not so much notice taken of the death of a mean, as of a noble, great, or rich person; so that for want of information or knowledg, one may easily be deceived in the number of each sort of persons. Next, the Vulgar sort use laborious exercises, and spare diet; when as noble