Often, when Saltpeter is involved, a Salamander is nearby. Here Lemery gives an insight into how to work what Fulcanelli called Stable Salt.
Together with a deep insight into how chemicals were produced in the seventeenth century. Consequently, with an interesting similitude with alchemical processes in preliminary works to volatilize salt. If you are not interested in Saltpeter per se, know that this part is also essential to get to the ancient processes to obtain Aqua Regia.
Sometimes used to decrease melting temperatures, sometimes helpful to raise loader metallic substances, and sometimes naturally rich in Secret Fire/Mercurius, Saltpeter is very often mentioned in Alchemy.
The Lemery end products, that’s to say, purified Saltpeter, Salt de Prunelle, Salt Polichreste, Strong Water, and fixation in Alkali, are different from those made in modern laboratories. Unlikely my two previous posts on the Glaser’s trainee, namely Lemery and the Spirits of Salt Armoniac and Lemery & the Spirits of Common Salt with Wine, here the reader should read more between the lines since these proceedings are less consequent. As well as more in a whole, I decided to unify the work on Saltpeter in a single long article.
Reading the aforementioned articles is essential to understand this part better, sparing me, and the foregoing readers, the repetition of the same concepts.
Nicolas Lemery, Cours de Chimie, Chapter XV or fifteenth, On Nitre or Saltpeter, page 283, my translation from original french: “Nitre is a salt saturated with an amount of the Spirit of Air which makes it volatile, it can be extracted from the stones and piles of earth obtained during the processes of ships demolishing. It is also found in mines and other humid places, caused by Air condensation, and it tends to bind to stones.
Page 284: Saltpeter is also sometimes procured from animal urine falling on stones and piles of the earth; someone has even thought all the Saltpeter comes from there, but we can see every day that it is extracted from places that have nothing to do with urine. This salt is a half volatile and half simile to rock salt, as we will see later.
Saltpeter is not easily inflammable, as believed by most chemists, but when it finds some sulfur in a fire, it tends to join and help to raise the volatile part; in a way, it serves as a vehicle.
Or, in the case it is thrown on some sulfur with coal, Saltpeter will produce a considerable flame; on the contrary, inside a red-hot crucible, it will not burn at all because it will not find any sulfur.
Page 285, Purification of Saltpeter: Have ten or twelve pounds of Saltpeter in an adequate amount of water, let the dissolution set and then filter it, then make it evaporate in a glass or earthen platter till half reduction or at least till it will appear as having a thin layer covering the surface. So bring your platter to a cold place, the less possibly agitating it, and let it overnight. You will find some crystals which must be removed from the liquor, then make this liquor evaporate again till the layer forms and bring it again in a cold place. You will find crystals again: go over with evaporations and crystallizations until you have extracted all the Saltpeter. During the last crystallization, you will have salt comparable to sea salt or rock salt, which has to be put aside to be served in particular eating. The first obtained crystals are those of purified Saltpeter. You may dissolve and purify the Saltpeter over and over in the water, and you can see every time all we have said about its purification from the sea salt.”
What’s roughly the difference between that kind of chemical salt volatilization and an alchemical one ( since our Mercurius is extracted utilizing salt volatilization)? In Alchemy, volatilizations must be performed in closed conditions to avoid missing anything. Chemical volatilizations in the open air are generic achievements of crystals, Saltpeter, of course. Still, Alchemy is more than a mere purification of Saltpeter and separation from the other salts.
Page 286: “ The refined Saltpeter is quite an aperitif, and helps cool down exciting behaviors, then eliminating with urines ( dosage can be found in the original page here produced).
Notes: The first Saltpeter purification to be done is the following. Roughly powder the stones and earth containing it; then boil in a large volume of water to dissolve the Saltpeter. Cool down the dissolution, then pour it on some ashes to make a lixiviation. In so doing, remove any greasy substance, pass the liquor over the ashes again, and let the whole evaporate and crystallize. Page 287: the same earth which has been cleaned from Saltpeter can be placed again in the Air and again discharged from Saltpeter, provided you let the necessary time Saltpeter again impregnate this earth.
The oblong crystals in which this salt can appear come from its volatile part since this is the last part to be crystallized and fixed, just like the sea salt, which takes shape. Saltpeter cannot be proficiently refined if it doesn’t contain a certain amount, similar to rock salt or sea salt. But in less quantity than before.
When Saltpeter is boiled at the utmost temperatures for a long time, a part of Spirits gets dissipated, and in the end, it remains a salt similar the sea salt or rock salt. That’s proving the Saltpeter is nothing more than a rock salt more impregnated with Spirits than the first one, as we have said when talking of principles.”
Along with the possibility of hygroscopic salts retaining some qualities from the air, in addition to water or even contained inside water, and here I’m talking of that Mercurius Universalis coming from Sun and Moon and hovering in the Air (1), what jumps to a trained eye is here the absolute Lemery’s disregard to every molecular purity. Note the same absence of interest among alchemists.
“Page 288: When one wants to have some salt crystallized, this must be dissolved in a suitable volume of water, since if it was excessive, they would cause the be too much weak and unable to coagulate; and if on the contrary, the water was less than suitable the crystals would be very poorly shaped. So to make them conform, one has to remove the platter from the fire; when you can see the thin layer appear above the liquor, this is a sign there is a little less moisture to keep the salt in dissolution, and so when put in a cool place there’s no lack of fixation. and among those, the volatile ones get crystallized in less time than the others.
The Saltpeter gets frozen since being acid; it burdens fluids which, because of their intense agitation, seize and make them precipitate in urines. Since the salts and sulfurs fill all the bodies, acids quickly fix and clog them.
Mineral Crystal, called Salt of Prunelle, page 289: crush two pounds of refined Saltpeter and put them into a crucible which you will place inside an oven on an intense fire. As soon as the Saltpeter melts, pour-over, at various times, one ounce of flowers of sulfur, and the matter will soon flame, and the more volatile spirits of Saltpeter will fly off: when most of the flames will lose power, the matter will remain melted and well bright. Take hold of the crucible helping yourself with pliers and overthrow it over a plain and clean bronze basin, which will be well heated before, to make sure that all humidity has gone: turn the basin to spread the salt while cooling; this is called Salt de Prunelle.
It is crucial to have it well pure, making it melt in a suitable volume of water, filtering the dissolution, and letting it crystallize, as we have already said about the purification of Saltpeter.
It is said to be better than refined Saltpeter as a medicine because of the presence of sulfur inside ( usage and dosage on the original page 290).Page 291. Notes: This preparation is called salt or stone de Prunelle or blackthorn, either because the salt extracted from blackthorns has little by little the same virtue and shape of the mineral crystal or because it is prescribed in case of hot fevers, whose heat is comparable to a red hot piece of coal, which is called Pruna. German people give it the shape of a blackthorn tinted in red with roses.
The ancients believed that it would be necessary to throw some flowers of Sulphur on the melted Saltpeter to make it more aperitif. Still, in so doing, depriving it of its spirits more penetrating than the sulfur raised with it; in this way, instead of making it more open and efficacious, it is denied to release its best.
It is easy to see this lousy purpose being one of those abating the sake of chemical medicine, failing to discover the composition of natural things instead of merely giving correctives. So I would recommend simply serving refined Saltpeter purified from its salt fixed three or four different times; as we have written, I assure you from my so frequent experience that it is far better than when prepared with sulfur.
Page 292. Salt Polichreste: Powder and mix equal parts of Saltpeter and common sulfur. Throw about one ounce of this mixture in a good crucible, which has previously been made red hot; it will be a considerable flame that is being passed; throw inside again the same amount of matter and go on like that till all your mixture is employed. Go on with the fire another four and five hours; take care that the crucible is always red hot, then overthrow the crucible on a bronze platter well dried at the fire. Then the matter is cooled down, get it powdered, and make it melt in a suitable volume of water; filter the dissolution and have it evaporated in an earthen or glass basin at a sand fire: you will have a very pure Salt Polichreste. What will remain in the filter must be rejected as useless. Use ad dosage on the original page.