changes of motions, and moving parts will either oppose or assist each other without transchanging. And truly, _Madam_, I wonder that your _Author_ doth condemn such Cordials made of Leaf-gold, Pearls, powdered precious Stones, or the like, and yet verily believe, that Amber, Saphires, Emeraulds, Beads, Bracelets, &c. outwardly applied or worn, can cure more then when inwardly taken; surely, if this be so, they cure more by Faith, then by Reason. But it seems your _Author_ regulates the actions of Nature to the artificial actions of his Furnace, which although sometimes they produce wonderful effects, yet not such as Nature doth; for if they cure one, they commonly kill ten; nay, the best of their Medicine is so dangerous, as it ought not to be applied but in desperate cases: Wherefore Wise Physicians must needs be Provident and Cautious when they use them. And so leaving them, I rest, Madam, _Your faithful Friend_ _and humble Servant._ [1] Of the disease of the Stone, _c._ 3. [2] _Ch._ Of the reason or consideration of diet. XXXIX. _MADAM,_ I will not dispute your _Authors_ opinion concerning the Plague of Men, which he says,[1] _doth not infect Beasts, neither doth the plague of Beasts infect Men_; but rather believe it to be so: for I have observed that Beasts infect onely each other, to wit, those of their own kind, as Men do infect other Men. For example: the Plague amongst Horses continues in their own kind, and so doth the Plague amongst Sheep; and for any thing we know, there may be a plague amongst Vegetables, as well as amongst Animals, and they may not onely infect each other but also those Animals that do feed on those infectious Vegetables: so that Infections may be caused several ways; either by inbreathing and attracting or sucking in the Poyson of the Plague, or by eating and converting it into the substance of the body; for some kinds of poyson are so powerful, as to work onely by way of inbreathing. Also some sorts of Air may be full of infection, and infect many Men, Beasts, Birds, Vegetables, and the like; for Infections are variously produced, Internally as well as Externally, amongst several particular Creatures; for as the Plague may be made internally, or within the body of a particular Creature, without any exterior infection entring from without into the body, so an external Infection again may enter many several ways into the body. And thus there be many contagious diseases caused meerly by the internal motions of the body, as by fright, terror, conceit, fancy, imagination, and the like, and many by the taking of poysonous matter from without into the body; but all are made by the natural motions or actions of animate matter, by which all is made that is in Nature, and nothing is new, as _Solomon_ says; but what is thought or seems to be new, is onely the variation of the Motions of this old Matter, which is Nature. And this is the reason that not