This is a famous book, but an odd one to modern eyes. Wikipedia calls it “… a fine example of pre-Baconian science.”, which might be correct but doesn’t mean much to most people. What it most obviously is is a recipes book, like the then popular books of secrets, on topics such as poisons, magnetism, metallurgy etc. But what it seems to do is align ‘natural magic’ with simply how the world works in and of itself, i.e. it isn’t occult i.e. hidden, in the old sense of the word. How important this was at the time I don’t really know yet.
However, on closer inspection, the term “natural magic” is clearly used as meaning not sorcery, which uses “foul spirits”, but rather knowing how nature works.
“I pass over other men of the same temper, who affirm that I am a witch and a Conjurer whereas I never wrote here nor elsewhere, what is not contained within the bounds of nature. Wherefore, studious readers, accept my long labors, that cost me much study, travel, expense, and much inconvenience, with the same mind that I publish them; and remove all blindness and malice, which are wont to dazzle the sight of the mind, and hinder the truth; weigh these things with a right judgment, when you try what I have written, for finding both truth and profit, you will think better of my pains.”
Within the bound of nature = natural magic = pretty much how everything works or how a physician heals his patient. It also says in the introduction:
From the first time it appeared, it is now thirty five years, and (without any derogation from my modesty be it spoken) if ever any man labored earnestly to discover the secrets of Nature, it was I; For with all my mind and power, I have turned over the monuments of our ancestors, and if they wrote anything that was secret and concealed, that I enrolled in my catalogue of rarities. Moreover, as I traveled through France, Italy, and Spain, I consulted with all libraries, learned men, and artificers, that if they knew anything that was curious, I might understand such truths as they had proved by their long experience. Those places and men, I had not the happiness to see, I wrote letters to, frequently, earnestly desiring them to furnish me with those secrets, which they esteemed rare; not failing with my entreaties, gifts, commutations, art and industry. So that whatsoever was notable, and to be desired through the whole world, for curiosities and excellent things, I have abundantly found out, and therewith beatified and augmented these, my endeavors, in “NATURAL MAGICK”, wherefore by earnest study and constant experience, I did both night and day endeavored to know whether what I heard or read, was true or false, that I might leave nothing unassayed; for I have oft thought of that sentence of Cicero, It is fit that they who desire for the good of mankind, to commit to memory things most profitable, well weighted and approved, should make trial of all things.
This obsession with testing things is not new; it is seen in Geber, and Roger Bacon discusses the forms of knowledge including that of testing what has been claimed. However he put a lot of weight on old experts and wise men, as well as on theology.
Porta on the other hand seems very much more modern, being sceptical and open minded.
The next few chapters discuss what magic is and how it works, with chapter 9 being “how to attract and draw forth the virtues of superior bodies”.
This is not new, it is important to emphasise that in the 16th century what we think of as a more modern approach was forming, but it was very clearly based in medieval thought and in turn upon classical thought.
Indeed I suspect that most people and organisations were still rather medieval in their outlook until the Enlightenment in the later 18th century.
Anyway, my main focus is of course on alchemy and metallurgy, and here it has something potentially interesting.
we get an English translation from the 17th century. In chapter 3 we find:
The chief and essential things that are of force to endue Brass with a whiter color, are these. Arsenic or Oker, that kind of Quicksilver that is sublimated, as the Alchemists call it, the foam or froth of Silver, which is called by the Greeks, Lithargyron. The Marchasite or Fire-stone, the Lees of wine, that kind of Salt which is found in Africa under the sand, when the Moon is full, which is commonly called by the name of Al-hali, Saltpeter, and lastly Alome. If you extract the Liquor out of any of these, or out of all of these, and when it is dissolved, put your Brass, being red hot, into it to be quenched, your Brass will become white. Or else if you melt your Brass, and as soon as it is molten, put it into such Liquor, your Brass will become white. Or else, if you draw forth into very small and thin plates, and pound those bodies we now speak of, into small powder, and then cast both the Brass that is to be colored, and the bodies that must collar it, into a melting or casting vessel, and there temper them together to good media, and keep them a great while in the fire, that it may be thoroughly melted, the Brass will become white.
So, allowing for vagaries of language, it looks like you have to dip your red hot brass into nitric or sulphuric acid. Simple, huh?
On the left 90% sulphuric acid, on the right, 5 molar nitric, that is not very concentrated but enough for my purposes.
A few minutes with a blowtorch to make the brass sheet and rod glow red hot, followed by quenching the brass sheet into the acids produced this:
So far I’m not impressed. At most there is a white deposit on the end dipped in the sulphuric acid, which might be down to salts caking on the metal. At the other end the nitric reacted with the copper and drew it out, leaving green salts.
Giving poor instructions is certainly one common medieval habit (But not one shared by everyone) that he could have done with getting rid of.
Modern descendants of this sort of book were around in the mid-20th century. I have an American version called “Fortunes in Formulas” which is not so different in recipe type than the 1879 edition of Spon’s “Workshop Receipts” that I also have. However the cultural gap is clear in the titles, but it would be an interesting blog post to compare them and search for medieval or earlier roots.
Anyway, I shall test some other recipes or parts of such recipes as I see fit. This sort of work helped fuel popular knowledge and chymical practises so is interesting in its own right. The recipes will have been stolen from alchemists, but how they are fed into popular culture is no doubt a topic of interest, and I expect some circled back into alchemy at some point.