Madam, for your health to be good, it is necessary for your cerebrum and cerebellum to distribute a fine, well-conditioned marrow, in the spine of your back down to your highness's rump; and that this marrow should equally animate fifteen pairs of nerves, each right and left. It is necessary that your heart should contract and dilate itself with a constantly equal force; and that all the blood which it forces into your arteries should circulate in all these arteries and veins about six hundred times a day. This blood, in circulating with a rapidity which surpasses that of the Rhone, ought to dispose on its passage of that which continually forms the lymph, urine, bile, etc., of your highness--of that which furnishes all these secretions, which insensibly render your skin soft, fresh, and fair, that without them would be yellow, gray, dry, and shrivelled, like old parchment. PRINCESS. Well, sir, the king pays you to attend to all this: fail not to put all things in their place, and to make my liquids circulate so that I may be comfortable. I warn you that I will not suffer with impunity. PHYSICIAN. Madam, address your orders to the Author of nature. The sole power which made millions of planets and comets to revolve round millions of suns has directed the course of your blood. PRINCESS. What! are you a physician, and can you prescribe nothing? PHYSICIAN. No, madam; we can only take away from, we can add nothing to nature. Your servants clean your palace, but the architect built it. If your highness has eaten greedily, I can cleanse your entrails with cassia, manna, and pods of senna; it is a broom which I introduce to cleanse your inside. If you have a cancer, I must cut off your breast, but I cannot give you another. Have you a stone in your bladder? I can deliver you from it. I can cut off a gangrened foot, leaving you to walk on the other. In a word, we physicians perfectly resemble teethdrawers, who extract a decayed tooth, without the power of substituting a sound one, quacks as they are. PRINCESS. You make me tremble; I believed that physicians cured all maladies. PHYSICIAN. We infallibly cure all those which cure themselves. It is generally, and with very few exceptions, with internal maladies as with external wounds. Nature alone cures those which are not mortal. Those which are so will find no resource in it. PRINCESS. What! all these secrets for purifying the blood, of which my ladies have spoken to me; this _Baume de Vie _of the Sieur de Lievre; these packets of the Sieur Arnauld; all these pills so much praised by _femmes de chambre_-- PHYSICIAN. Are so many inventions to get money, and to flatter patients, while nature alone acts. PRINCESS. But there are specifics? PHYSICIAN. Yes, madam, like the water of youth in romances. PRINCESS. In what, then, consists medicine? PHYSICIAN. I have already told you, in cleaning and keeping in order the house which we cannot rebuild. PRINCESS.