5. Q.–Which is the most noble salt?
A.–If you desire to learn this, descend into yourself, for you carry it about with you, as well the salt as its Vulcan, if you are able to discern it.
6. Q.–Which is it, tell me, I pray you?
A.–Man’s blood out of the body, or man’s urine, for the urine is an excrement separated, for the greatest part, from the blood. Each of these give both a volatile and fixed salt; if you know how to collect and prepare it, you will have a most precious Balsam of Life.
7. Q.–Is the property of human urine more noble than the urine of any beast?
A.–By many degrees, for though it be an excrement only, yet its salt hath not its like in the whole universal nature.
8. Q.–Which be its parts?
A.–A volatile and more fixed; yet according to the variety of ordering it, these may be variously altered.
9. Q.–Are there any things in urine which are different from its inmost specific urinaceous nature?
A.–There are, viz., a watery phlegm, and sea salt which we take in with our meat; it remains entire and undigested in the urine, and by separation may be divided from it, which (if there be no sufficient use of it in the meat after a convenient time) ceaseth.
10. Q.–Whence is that phlegm, or insipid watery humidity?
A.–It is chiefly from our several drinks, and yet everything hath its own phlegm.
11. Q.–Explain yourself more clearly.
A.–You must know that the urine, partly by the separative virtue, is conveyed with what we drink to the bladder, and partly consists of a watery Teffas (an excrementitious humour of the blood), whence being separated by the odour of the urinaceous ferment, it penetrates most deeply, the saltness being unchanged, unless that the saltness of the blood and urine be both the same; so that whatsoever is contained in the urine besides salt is unprofitable phlegm.
12. Q.–How doth it appear that there is a plentiful phlegm in urine?
A.–Thus suppose; first, from the taste; secondly, from the weight; thirdly, from the virtue of it.
13. Q.–Be your own interpreter.
A.–The salt of urine contains all that is properly essential to the urine, the smell whereof is very sharp; the taste differs according as it is differently ordered, so that sometimes it is also salt with an urinaceous saltness.
14. Q.–What have you observed concerning the weight thereof?
A.–I have observed thus much, that three ounces, or a little more, of urine, taken from a healthy man, will moderately outweigh about eighty grains of fountain water, from which also I have seen a liquor distilled which was of equal weight to the said water, whence it is evident that most of the salt was left behind.
15. Q.–What have you observed of its virtue?
A.–The congelation of urine by cold is an argument that phlegm is in it; for the salt of urine is not so congealed if a little moistened with a liquid, though it be water.
16. Q.–But this same phlegm though most accurately separated by distillation, retains the nature of urine, as may be perceived both by the smell and taste.
A.–I confess it, though little can be discerned by taste, nor can you perceive more, either by smell or taste, than you may from salt of urine dissolved in pure water.
17. Q.–What doth pyrotechny teach you concerning urine?
A.–It teacheth this, to make the salt of urine volatile.
—Eirenaeus Philalethes, “The Secret of the Immortal Liquor Called Alkahest or Ignis-Aqua” from Collectanea Chemica: Being Certain Select Treatises on Alchemy and Hermetic Medicine