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Chemistry Index

Chemical Element Identification Timeline
History of Phosphorus : Introduction and Timeline

History of Science and Technology Index

Robert Boyle: Biography

Characters involved in the Phosphorus Story

Hennig Brand (1630 - c. 1710)
Johann Kunckel (1630 - 1703)
Johann Daniel Krafft (1624 - 1697) and Gottfried Wilhelm Leibniz (1646 - 1716)
Johann Joachim Becher (1635 - c. 1682)

Transcripts of Publications (1677 - 1853)

Aerial Noctiluca : Robert Boyle 1680

Icy Noctiluca : Robert Boyle 1682

An Account of four sorts of factitious
Shining Substances : Robert Boyle 1677

A Paper of the Honourable Robert Boyle's,
Opened Since His Death (1692)

Some Observations made upon an Artificial
Shining Substance : Robert Boyle 1677

Extracts from John Evelyn's Diary 1681 and 1685

Experiments made with the liquid and of the solid
Phosphorus : Frederick Slare 1681

Extract from Experiments of the Luminous
Qualities of Amber : Samuel Wall 1708

On the Discovery of Phosphorus and a
Biography of Ambrose Godfrey
Hanckwitz : Joseph Ince 1853

An Extract from "An Account of some
Experiments upon the Phosphorus Urinæ"
by Ambrose Godfrey Hanckwitz 1731

Other Information

The Chemical Equations involved in the Luminescence of Phosphorus


Robert Boyle

Robert Boyle


Ambrose Godfrey Hanckwitz and the Crosey-Crucian

Hanckwitz4 told an amusing story (at least from an outsider's point of view) about a German alchemist who Boyle was remunerating to make gold (transmutation). Boyle asked Hanckwitz to accommodate this alchemist in his lodgings (and, presumably, share Hanckwitz's laboratory). At this time Hanckwitz was feeling sorry for himself - not only was he supplying Boyle with phosphorus but he was also following other experiments for the alchemist that were set up in his own lodgings, such as mercury fixation of lead, the separation of sulphur from animals (birds) and the resuscitation of plants. In later years, Hanckwitz described himself at that time as "a poor beginner and a servant too".

Boyle had asked Hanckwitz to report back on the progress of the alchemist which was non-existent. The alchemist put his lack of success down to loneliness due to the absence of his wife and Boyle obliged by paying for her trip to England. The Hanckwitz household, consisting of a one bedroomed apartment, was getting over-crowded. Boyle heeded Hanckwitz's complaints and paid for new accommodation for the visitors. However, the transmutation was not forthcoming and Boyle cut the alchemist's salary. Since Hanckwitz had been put in charge of paying the salary, the alchemist rowed with Hanckwitz and the alchemist's wife followed Mrs. Hanckwitz in the street shouting insults in German. (Hanckwitz describes the alchemist's wife as a "a terrible bawling creature" and expresses his relief that she harasses his wife in German rather than English, particularly as one of the accusations was that Hanckwitz had been cheating Boyle!). Eventually Boyle stopped all payment and refused to see the alchemist in person. One last row followed, after which the two visitors disappeared from the Hanckwitz's lives.

There are many sources who believe this unhappy alchemist was Johann Becher. Some even suggest that Hanckwitz had been a student of Becher's that Becher recommended Hanckwitz to Boyle and that Becher had some input about phosphorus production. There is no evidence for any of these outcomes. Although Johann Becher was in London between 1680 and 1682, he had influential patrons, including Dickinson and Boyle, he had been presented at court and he had worked for Prince Rupert and John Maitland, Duke of Lauderdale. It is highly unlikely that Hanckwitz's unwelcome alchemist and Johann Becher are one of the same. Likewise, although not improbable, Hanckwitz's youth and his previous employment in London would not indicate that he had had any contact with Becher before he started working for Boyle. The only hint that Hanckwitz gives to the alchemist's identity is that he was a "Crosey-Crucian" (Rosicrucian) and there is no documented evidence that Becher was ever in this sect. Finally, in Philosophical Transactions Number 428 (April, May, June 1733) An Account of the Experiments upon the Phosphorus Urinae, Hanckwitz makes reference to one of Dr. Becher's experiments - brick-earth mixed with any fat or oil and calcinated in the fire, he hath produced iron; it is highly unlikely that Hanckwitz would have used this example if Becher had been his unwelcome lodger.

4Joseph Ince wrote a biography of Ambrose Godfrey Hanckwitz published in three parts in Pharmaceutical Journal and Transactions 1858 - 1859. He was able to refer to Hanckwitz's original papers and journals that have since disappeared. Ince's biography can be accessed through this link.

On the Discovery of Phosphorus and a
Biography of Ambrose Godfrey
Hanckwitz : Joseph Ince 1853



Icy Noctiluca

Cover of Robert Boyle's "Icy Noctiluca"
the link below leads to the full text
and opens in a new window.
Icy Noctiluca : Robert Boyle 1682




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Robert Boyle and his Assistants: Their Role in the Phosphorus Story

Robert Boyle's interest in luminescent materials began a long time before he was introduced to phosphorus in 1677. Unlike many of those involved in the phosphorus story, Boyle was not looking to make money - he was already very wealthy. Boyle was a devout Christian and saw luminescence as a gift from the Creator who had given one whole day to "let there be light". This alone warranted a thorough investigation and detailed record of his subsequent experiments on this new, shining miracle.

In 1677 Johann Daniel Krafft was invited, (and paid a substantial fee), by King Charles II to the London court to demonstrate "das kalte feuer". On 15th September Krafft made the journey to Pall Mall to demonstrate his product to Robert Boyle and other members of the Royal Society. He made a return visit the following week on 22nd September. Both of these visits were recorded by Boyle and his account, 'Some Observations made upon an Artificial Shining Substance', can be accessed via the link to the left.

In a letter to Dr. John Beale, a friend of Boyle's living in Somerset who shared an interest in phosphorescent materials, Boyle describes Krafft's visit in September 1677 and relates that Krafft only told Boyle that the phosphorus he demonstrated was "of the body of man". Boyle goes on to write that he was unable to pursue his investigation for a few months because of ill-health and law suits. When he did begin his work on phosphorus he seems to have been put on the wrong track by "an arcana1" information that came "from overseas".

1 Arcana = secret

These first attempts were probably made in late 1678 or early 1679. Boyle had guessed correctly that urine was probably the starting point to produce phosphorus. It is interesting to speculate where this secret information from overseas may have originated. At least three individuals were producing phosphorus on the continent in 1678/79, Hennig Brand, Johann Kunckel and, by that time, Gottfried Leibniz, the latter would seem a likely candidate. It is known that Leibniz corresponded with Boyle's employee Frederick Slare from as early as 1673 so it quite possible that Leibniz did communicate a possible recipe, either directly or indirectly, to Boyle2.

2In 1679 Johann Kunckel traded his recipe with Wilhelm Homberg in exchange for another alchemical 'secret'. In the same year Homberg arrives in England, bearing a letter of introduction written by Gottfried Wilhelm Leibniz, and met Robert Boyle. It is possible that Boyle and Homberg traded information and that Homberg helped Boyle prepare phosphorus. Ambrose Godfrey Hanckwitz recorded "At last our grand Boyle got it by lytterall correspondence and word of mouth out of Saxony".

Around 1678, when Boyle began his attempt to make phosphorus, he was working with Slare and one of his chemical assistants was a certain Mr. Daniel Bilger who had been in Boyle's employ for at least two years3. Bilger was joined, probably in 1679, by a nineteen year old named Ambrose Godfrey Hanckwitz who had already worked as an assistant chemist in London on his arrival from Germany.

3Robert Hook's diary for 19 June 1676 - 'to Boyle's with Slayer, Pilgar (note: probably refers to Bilger) and Pappin'.

Robert Boyle's laboratory (in fact, laboratories, since he maintained at least two in London and maybe more) were very active places and he surrounded himself with a numerous support team. Following a riding accident in Ireland that provoked a fever, Boyle was left with weak eyesight and trembling hands. His entourage would have included individuals who could write his laboratory notes and papers. At the end of the 1670's his team would have included Frederick Slare and Samuel Wall. These were specialized assistants, roles that Robert Hooke and Denis Papin had filled in the past, who were capable of helping to design and handle complex apparatus. Boyle also employed laboratory assistants and operators. Boyle put a lot of trust in his assistants' ability to accurately record their observations. He would only step in himself if results were inconsistent or there were variations in the observations of two operators. In this case Boyle would be present when the experiment was repeated, as he explained, "for my fuller satisfaction".

All of Boyle's laboratories would have been hives of industry. There would have been a number of chemical assistants working on a variety of projects and these would have involved different chemical processes - distillation, production amalgams of metals, purifications - and, in each case, the assistant would have been required to record all of his observations in detail. He would also have employed full-time expert glass blowers to make the delicate glassware to his specifications. The operators and technicians may have been present to work the complex equipment. Add to this the frequent visitors, specialized instrument makers, chemical suppliers and pharmacists. Boyle's employees are likely to have been on a limited contract and any extension would have been dependent on their performance. Boyle would have regarded all of his workers as simply following out his orders and this led to a certain amount of resentment, particularly on the part of the more able, trusted and qualified of them. Boyle's paper's rarely mention any of his collaborators by name. He refers to his "skillful assistant" and sometimes blames a "laborant", as he often refers to them, for any misdemeanor during an experiment.

Boyle's "Aerial Noctulica" is published in 1680 and so he was already producing phosphorus by then, probably from 1679. In this paper, Boyle includes some of his letter to John Beale and from this correspondence we discover that it was a German visitor (who Boyle only refers to as A.G. MD, "countryman, if I mistake not, of Mr. Krafft,") that put him on the right track by suggesting higher temperatures to complete the distillation. Some researchers suggest that this visitor was Hanckwitz since he went by the name of Ambrose Godfrey when he resided in England. However, this is unlikely since Hanckwitz did not have a doctorate and Boyle clearly states that his visitor returned home soon after. Also, Hanckwitz was young and only a laboratory assistant and, as such, unlikely to have had the private audience with Boyle that this letter suggests.

Samuel Wall reports that, in 1680, Boyle was unhappy with the quantity of phosphorus his assistant, Mr. Bilger was producing. Wall reported to Boyle that he had seen small pieces of phosphorescent material in "dry matter dug up from fields where night men emptied their vessels". Bilger was ordered to try this solid waste as a source. According to Wall, who even lodged with Bilger in Mary-Le-Bone Street, Piccadilly for a while, this source on its own did not prove successful but when "another material" was added, together the two starting ingredients produced a more generous supply of phosphorus.

The fact that Samuel Wall needed to move in with Bilger indicates that Boyle must have set up a laboratory, perhaps specifically for the production of phosphorus, close by to Bilger's lodgings. Although Boyle had a laboratory at the back of his sister's house in Pall Mall, he would most certainly have outsourced the pungent process needed to produce phosphorus. At some point Bilger started to work for himself as well as for Boyle. Wall reports that Bilger started selling his product. Whether Boyle was aware that his assistant was using his laboratory facilities and, presumably, his raw materials to line his own pockets is unknown5. Wall reports that Bilger became a rich man from the proceeds and left England: In a 1708 letter to Dr. Sloane, the secretary of the Royal Society, Wall states ".... For while I was at his House, I often saw him make it, and sell it for six Guineas, and six Louis d'Ors an Ounce, whereby he got so much Money, that, I believe, he thought himself above his Business, and quickly left England; so that we lost an Honest and Ingenious Chymist, and Mr. Boyle a Faithful and Industrious Servant". (There is a link on the left to a transcript of Wall's account of this story).

5 According to Joseph Ince who had access to original documents, Hanckwitz had "heard of battles" which could indicate that Boyle was not too happy about Daniel Bilger's sideline activities!

Ambrose Godfrey Hanckwitz found himself promoted. He and his wife were lodged in Chandos Street, Covent Garden. It is reported that the laboratory Hanckwitz worked in was close by and this was, presumably, the same laboratory that Bilger had used. In later years Hanckwitz reported that he had been instrumental in improving the phosphorous yield by suggesting that urine be mixed with faecal matter. This was the big secret that made Hanckwitz very efficient at producing high quality phosphorus for Boyle which led to Boyle's paper "Icy Noctiluca" in 1682. It is, however, interesting that, in the "Icy Noctiluca", Boyle states "I will not positively affirm, that the matter I employed is the very same that was made use of by the ingenious German chymists, in their noctiluca; for some inquisitive men have told me, that the Germans mix two or more distillable materials; whereas I employed but one substance capable of distillation."

The full texts of "Icy Noctulica", "Aerial Noctulica" and Boyle's account of Johann Krafft's 1677 visit are available through the links to the left. The only change to the original texts is an attempt to "translate" them in modern English. There are some notable passages, such as those that describe the injuries that Boyle's assistant, presumably Hanckwitz, received through handling phosphorus and Boyle taking a sample of phosphorus to bed with him as his nighttime companion. These papers make very interesting reading and give extremely thorough descriptions of all the experiments, or trials, Boyle carried out on his three types of phosphorus - icy, liquid and aerial.

After the publication of "Icy Noctulica" in 1682 Boyle appeared to have lost interest and he moved on to other things. Hanckwitz, however, left Boyle's employment in 1683 (apparently with Boyle's consent and financial backing) and continued using the laboratory in Covent Garden to produce white phosphorus. He sold to buyers not only in London but across Europe. His prices were £3 per ounce retail and 50 shillings per ounce wholesale. His customers were pharmacists, alchemists, natural philosophers and individuals who, like Krafft, made their money from demonstrating phosphorus to the wealthy. Unfortunately, phosphorus was seen as a panacea for cures to all ailments and its use in prescribed medicines did more harm than good, as Johann Kunckel had already discovered.

By 1707 the Ambrose Godfrey Hanckwitz pharmaceutical firm moved to new premises in Southampton Street where Hanckwitz worked until his death in 1741. His new establishment was called the "Golden Phoenix" and the 1680 date above the door indicated the year Hanckwitz had first made phosphorus for Boyle rather than the year the "Golden Phoenix" first opened its doors. Hanckwitz was elected as a member of the Royal Society in 1730 after the publication of several papers on phosphorus in Philosophical Transactions. His "English Phosphorus" prepared by a method he had perfected over the years had a monopoly on the market because of its reputation. In a 1733 memoire to the Royal Society, Hanckwitz (aged around seventy three) stated "I know myself to have been for these forty or fifty years, that is, ever since I left the laboratory of my master the Honorable Mr. Boyle, the only person in Europe able to make and produce in any quantity the true solid phosphorus". Hanckwitz kept his perfected recipe a close secret and his paper only included a somewhat vague description of his method. Having had over fifty years to perfect his method, Hanckwitz 's description of Brand's produce as a 'dark, unctuous, dawbing mass' is just a touch uncharitable6.

6 It is interesting that, on another occasion, Hanckwitz writes "...... all observations have greatly contributed towards my better perfecting that wonderful preparation the phosphorus glacialis of which, since the death of Mr. Bilger, I may, without vanity, call myself, for near these forty years, the sole maker in Europe." This would suggest that Bilger continued his lucrative production of phosphorus after he left England.

In 1929, almost two hundred years later, Hanckwitz's recipe is discovered in Germany by the scientific historian Dr. Max Speter. It appears that the London court physician in 1735, a certain Dr. Hampe, took advantage of the elderly and forgetful Hanckwitz and interrogated him into revealing the secrets of his method! These included the distillation of a mixture of faeces and urine, the fact that all operations were conducted under water, especially pouring and cutting the product after pressing it through leather.

It is also interesting to consider Frederick Slare's association with Boyle. Although he was born in England, Slare's father was German (original family name being Schloer). Slare was sent to the continent to further his education and graduated with an M.D. from Utrecht University. Some sources state that Slare began to work for Boyle in 1666 which seems a bit early since it would have made him only about eighteen years old. He was certainly involved in the initial work on phosphorus in Boyle's laboratory but, apparently, not for long.

However, even when he had left Boyle's employment, Slare continued to study phosphorus. Slare was already presenting papers on phosphorus to the Royal Society in 1679 and followed this with a presentation and a paper in 1681. Since Boyle left Slare a gift in his will, it is likely that Slare's branching out on his own caused Boyle any concern. Whether he was making phosphorus himself or, by that time, buying it from Bilger and later Hanckwitz, is unknown (although his "An account of Several Experiments made with the shining substance of the liquid and of the sold Phosphorus" from December 1681 (see the link on the left) he states "I shall now only give you an account of the two or three experiments about the Phosphori of my own preparation").

Unlike Boyle, whose investigations into phosphorus were concrete and experimentally based, Slare was more fascinated by the philosophical and alchemical aspects. He believed that the discovery of phosphorus represented the "flamma vitalis" or the vital flame of life. In December 1681 he wrote "the learned Willis (were he alive) would rejoice to see such a product of our bodies, who was very confident of something igneous or flammeous or very analogous to fire, that did kindle and impregnate our blood". The diarist, John Evelyn, was present for the Royal Society meeting on 4th August 1681 and he recorded "(Slare) ..... affirmed it to be chymically and with extra-ordinary preparation composed of urine and human blood which gives great light to Dr. Willis etc. notions of the flamma vitalis which animates the blood and is, for ought we know, the animal life itself of all things living; It is certainly a most noble experiment first excogitated and hinted (as this Doctor confessed) by Mr. Boyle ....". (The reference to human blood in this extract is particularly interesting). Evelyn went on to recount that he had, rather recklessly, covered his face in phosphorus and "I appeared in the dark like the face of the moon, or rather like some spirit, or strange apparition" and, not so surprisingly, "(It) ......had an urinous smell." (See the link to the left to the full text of Eveln's diary entry).

The phosphorus story is surrounded in mystery and there are many questions as yet unanswered. For example, on 14th October 1680 Robert Boyle deposited a paper with the secretary of the Royal Society with precise instructions that it would not be opened until after his death. The paper was folded and had three impressive seals, that of Boyle and those of the two witnesses to it having been deposited. When the paper was opened in 1692 it must have given rise to a lot of disappointment. It contained Boyle's recipe for making phosphorus that was almost identical to the one he published in "Aerial Noctulica" in 1680 and, as Frederick Slare pointed out, in the preceding twelve years chemists had succeeded in finding less complex and time consuming methods.

In 1719, aged around sixty nine, Hanckwitz met Georg Ernst Stahl in Berlin who told him that Johann Krafft had obtained the recipe from Hennig Brand. Krafft claimed to have given the recipe to Boyle and Hanckwitz himself is reported to have said at some point that Krafft had passed the recipe to Boyle. These claims are certainly untrue. Gottfried Leibniz, who knew Krafft well, wrote to the French Académie des Sciences stating that Krafft, who was really only a showman, was never in possession of the recipe which means that he could not have given it to Boyle. However, Boyle indicates in "Aerial Noctiluca" that he did have some information and hints from abroad but he is secretive about his sources.


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