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Everburning Lights
(ascribed to Trithemius)

Hearupon follows a modern chemical experiment.

Interpretation and testing done by Sam Van Oort, assistance from Adam McLean

Note: if you have laboratory grade sulfur, you can probably skip to step 8 and use it in place of prepared sulfur.

1)      Heat alum (potassium aluminum sulphate dodecahydrate) over a Fischer or Bunsen burner in a crucible, leaving sufficient space in the crucible for the alum to bubble. The water will be driven from the alum within a few hours, yielding anhydrous potassium aluminum sulphate.

2)      Crush equal masses of the anhydrous alum and sulfur in a mortar and pestle, and put it into pyrex beaker, filling the beaker only ¼” to ½” deep.

3)      Place the beaker on a good hotplate, and cover with a crucible so that the beaker has a partial seal. It is essential that you do the following in a well-ventilated area or a hood, as toxic sulfur dioxide will be produced by the following step.

4)      Put water in the crucible. Heat the beaker on the hotplate’s highest setting (400-500o C if possible).   Let the sulfur collect on the underside of the crucible and walls of the beaker, placing water on the top of the watchglass if it boils away. BE CAREFUL NOT TO OVERFLOW. When all the sulfur has been driven from the mixture, leaving a grey powdery mess on the bottom of the beaker, is it prepared. The original process & practica says that this may take up to 8 hours. I have found that it can be done in 1-2 hours.  

5)      Scrape off the sulfur from above and mix with borax (boric acid or sodium borate) in a 2.5:1 ratio by mass.   Finely grind the mixture in a mortar. Put it into a flat recrystallizing glass.

6)      Pour ethanol on it, & extract it in ashes softly to the oil, pour it upon again, extract it to the oil, pour it upon again & draw it of again.  

7)      Take a little of the sulfur, put it on a red hot copper plate, (you may use a hot plate alternatively). When it flows like wax without smoking then is it prepared. If not, boil off more of the ethanol, till it passes the above test

8)      Now take asbestos fibers and make a wick as long as a little finger, and half as thick.   Fold it about with white silk, and put it thus whole into a Venetian little glass (vial?), and pour powdered prepared sulfur around it.    

9)      Place this in a container of sand on a hotplate set low, with the silk-wrapped asbestos continually in the prepared sulfur. Let it warm a day and then over-night. I suspect that the sulfur is supposed to melt into the wick.

10) Take the wick out, and put it into such a vial or flask, so that that tip peeps out a little, and add to this the prepared “incombustible” sulfur.

11) Place the glass into the container of hot sand till the sulfur melts, and cleave beneath and upward about the wick, that it be seen but a little above.

12) Light the wick with a flame and it will start burning. The sulfur will keep flowing. Take the light and place it where you want, and it will (supposedly) burn forever.

Ancient Formulae:

Everburning Lights
ascribed to Trithemius.

Two eternall unquenchable burning temporall lights of Mr Trittemio Abbot at Sponheim, described by the hande of Bartholomeus Korndorffer.

Two unquenchable eternall lights are founde and to be seen hearin, which I Bartholomeus Korndorffer have written of a disciple of Mr Trittemius Abbot of Sponheim, which did affirme with an oath that they were never published nor opened before, only that his Mr the Abbot had bestowed one of them unto a great potentat. this famous Maus Trittemius, which lived in time of the great Imperiour Maximilian the first, and none like unto him was to be founde in his age, hath done much good with his artes, not mingled with divilish worcke, as some malicious men doe accuse his, butt he did knowe all what was done in the world of what he desireth by the starres of ministerie, he hath also tolde of things to come manie times. Once as was travaling, came to S. Moritz, and found an acquaintance to whome I spoke, he was glad to see mee, he invited mee to dinner, and another named servatius Hohel, which had been with the Abbot at Sponheim and served him 12 years. He wwas vere civill, yet sometime he spoke a word of this arte. Now as wee came together, and dinner beying past Mr Hohell desireth mee to goe with him to his chammer, which i did discoursing of diverse matter of artes and seying he was an antient man, I desired to leave him allone to his studie butt he would not left mee, and bespoke a meale by his hostess, which wee two did take in his chammer. Mr Hohel did bestowe uppon mee that time, the handwriting of Mr Trittemius whearin thease two incombustible lights were wrytten, and some magick peeces, which I did trye 7 prouve affterwards & founde them to be vere true & right. Mr Hohel tolde mee also that his Mr Trithemius had bestowed one of those lights unto this great potentat the Emperour Maximilian, and placed it in a glass in his chammer, which the sayd potentat had keept vere well, and many had seen the lightning thereof. After that a sickness aryseth that the Emperour did departe from that place, & came not to this place again in 20 years: but as he came theather at the least, Mr Trittemius beying dead long before, he remembered this light & went presently to see it, which was found theare with all tokens unquenchable as Mr Trittemius had lefft it, & the people of that castel tolde the Emperor that they had seene continually a lightning in that place, licke a lampe in a church. Wherefore this Emperour lefft the light years still burning wheare it shall surne still at this daye, which is a great secret in this worlde. the Emperour Maximilian hath given 6000 crownes for those temporall everlasting lights.

Hearuppon followeth the process & practica.

Take 4 unces of sulphur, & so much of calcyned alume, bruise them together, put it into an earthen sublimatorie, place it into a coale fier, well lited, let the sulphur ascend through the Alume, and in 8 houres is it prepared.

Thearof take at the lesse 2 1/2 unces, and one unce of good christallick venetian porras, bruse them two small togeather, put it into a flat glasse that it may lye flatly, poure uppon it a stronge sharpe 4 times distilled spirit of wine uppon it, & extracte it in ashes sofftly to the oyle, poure it uppon again, extracte it to the oyle,poure it uppon again & drawe it of agayne; take a litle of the sulphure, laye it uppon a red hott copper plate, and when it floweth like wax without smoking then is it prepared, if not then must thou extract theareof more of the spirit of wine, till it sustineth the proove & it is prepared.

Nowe take alumephume, make therof a top not as long as a little finger, and halfe as thicke, foulde it about with whyte silke, put it thus whole into a venetian little glasse, & joyne thearunto of the prepared sulphure, place it a day & night in hott sande, that the top be continually in the sulphur. Nowe take the top thearout, and put it into such a glasse, that the top looke out a little, adde thearunto of the prepared incombustible chyburals, place the glasse into hott sand till the sulphure melteth, and cleaveth beneath and upward about the top, that it be seene but a little above, kindle the top with a common light, & it beginneth to burne presently, and the sulphure remaineth flowing, take the light and place it wheare you wilt, and it burneth continually for ever.

Sources: -- has primarily spiritual stuff -- order of discovery of substances -- names for chemicals - Archaic chemical names - alchemical substances - alchemy terms – more alchemical names for cpds - yet ANOTHER alchemy terms dictionary
The Handbook of Chemistry and Physics (CRC)

Proposed Mechanism:

The alum is heated (“calcined”) to make it anhydrous.
This is added to the sulfur so that it will absorb water from it and the sulphur won’t yield sulfuric acid when heated.
Steps 3-5 are just sublimation purification of the sulfur and subsequent collection.
I am unclear as to the role of the borax, but I suspect that it is supposed to react with impurities in the sulfur.
The pouring upon of ethanol (“spirit of wine”) will dissolve the sulfur, as it is slightly soluble in ethanol, and when the ethanol is boiled off, purer sulfur will be left.
Thus, the sulfur is further purified.
I hypothesize that the sulfur used by the alchemists was of such execrable quality that it must be purified before use.
The functional mechanism of this light is that molten sulfur is drawn up the asbestos wick (which never burns up, because it is asbestos) and combusts with air to yield SO2 gas. The heat would keep the sulfur molten, and since SO2 is a gas, there is no ash or build up to snuff the light. The light should burn with a purple flame until all sulfur is exhausted.
By keeping the rate of combustion low, the light can burn for a really long time.

Photographic record of experiment

Calcining the Alum

Flowers of Sulphur

Subliming the mixture

The light