Sometime around 1669, in a workroom in Hamburg, a former soldier named Hennig Brand heated the boiled-down residue of stale human urine until his furnace glowed red. What came over into the receiver was a white, waxy solid that shone in the dark and caught fire by itself.
He had been looking for the philosopher's stone. What he had found was phosphorus, and Britannica credits him as the first known discoverer of an element. Gold, iron and sulfur were inherited from prehistory. Brand's substance has a place, an approximate year and a name attached.
That is nearly all that is firm. The rest, including the famous quantities of urine, deserves a closer look.
A man with almost no biography
Brand left very little behind. Fritz Krafft, the historian of science whose 1969 paper in Angewandte Chemie remains the most careful account, states flatly that not even approximate dates of birth and death are recorded. Reference works often print "about 1630" for his birth and either 1692 or 1710 for his death, and those figures are estimates, not records.
What the sources agree on is thinner but vivid. He had served as an army officer in his youth. In Hamburg he practiced medicine without much in the way of formal qualification (Britannica calls him a self-styled physician) and traded in chemical remedies. He married a widow with money and a son from her first marriage, and her fortune paid for the laboratory.
The year 1669 itself rests on later testimony, since Brand published nothing. Leibniz, writing decades afterward, put the discovery around 1677. Krafft argues that this refers to the moment the secret got out, and that Brand had no motive to backdate his own find. "Around 1669" is the honest form.
Why urine, and how it worked
The choice of raw material was not eccentric by the standards of the trade. Urine was golden, which counted as a clue. Krafft suggests Brand was following a printed recipe that promised to turn silver into gold by way of distilled urine, though he adds that the exact source will probably never be identified.
The method, as later reconstructed, went roughly like this. Urine was left to stand until it stank, then boiled down to a thick syrup. The residue was heated in a retort, gently at first and finally as hard as the furnace allowed, for hours. Late in the run a glowing vapor came off, which was led into cold water and condensed to a solid.
The chemistry is not mysterious now. Urine carries dissolved phosphates. At red heat, carbon from the charred organic matter strips the oxygen from them and frees the element. Brand called the product his cold fire, according to Krafft, and seems to have believed he had isolated the element of fire. The name phosphorus, Greek for light bearer, was the general term of the day for anything that glowed in the dark.
How much urine?
Popular accounts are confident about the numbers. One figure, repeated on Wikipedia and across the internet, is about 1,500 gallons, or 5,500 to 5,700 liters, for 120 grams of phosphorus. Another, printed in a Royal Society of Chemistry education article, is 50 buckets for the same 120 grams.
These cannot both be right, unless the buckets held more than 100 liters each. And neither can be traced to Brand. Krafft is explicit that Brand never published a word about his phosphorus and that none of his surviving letters reveals the method, let alone a tally of what went into the pot. The figures look like back-calculations from a plausible yield, and they should be read as illustrations of scale, not as measurements.
The scale itself is believable, since the process is wasteful. The one documented quantity comes from later in the story. When Brand was brought to Hanover to manufacture phosphorus for the duke, the plan was to supply him from the local garrison, and Krafft cites reports of about 100 casks, which he converts to roughly 13,140 liters. Soldiers' urine by the barrel is in the archive. The 1,500 gallons is not.
The secret gets out
Brand kept quiet for several years. By 1676 he needed money, and two visitors had seen the glowing substance: Johann Kunckel, a court chemist, and Johann Daniel Kraft, a merchant from Dresden. Kraft moved faster. The Neue Deutsche Biographie says he bought the secret for 200 Reichstaler, and the Royal Society of Chemistry article adds that the deal came with a condition that Kunckel was not to be told.
Kraft then took samples on tour, showing them at Berlin in April 1676, at Hanover in 1677 and in London. Krafft doubts he ever made the stuff himself. Kunckel, who had been shown the experiment in Hamburg, struggled for some time, wrote to Brand asking for clearer instructions, eventually succeeded, and afterward presented himself as the discoverer. For more than a century much of Europe believed him.
In London, Kraft showed his samples to Robert Boyle and let slip one clue, that the principal matter came from the body of man. That was enough. Boyle and his young German assistant Ambrose Godfrey Hanckwitz worked out a version using urine syrup mixed with fine white sand. The Royal Society's archive still holds Boyle's manuscript of the method, dated September 30, 1680, deposited sealed with the secretaries and opened only after his death. Britannica says Boyle rediscovered phosphorus independently. Given the hint, "with a head start" is fairer. Hanckwitz went on to make it commercially and was shipping it to Germany by 1685.
Leibniz and the garrison
The man who saved Brand's credit was Gottfried Wilhelm Leibniz, then in the service of Duke Johann Friedrich at Hanover. He sought Brand out, negotiated a contract under which Brand would reveal the process in confidence, and brought him to Hanover twice. The first stay lasted five weeks, at ten Reichstaler a month, which Brand complained could not keep his family. On the second, in 1679, he fell ill. The duke died that December and the payments stopped. A letter of April 1682 shows Brand still demanding what he was owed. The Neue Deutsche Biographie has him going home sick and broken, after which the record goes silent.
In 1710 Leibniz published a short Latin history of the invention in the journal of the Berlin academy, naming Brand as the discoverer. It is largely because of that paper that the name survived at all.
The painting
The image most people now attach to the story was made a century later and is not a portrait. In 1771 Joseph Wright of Derby exhibited a large canvas, about 127 by 102 centimeters, under a title that begins "The Alchymist, in Search of the Philosopher's Stone, Discovers Phosphorus." It hangs in Derby Museum and Art Gallery.
Wright never names Brand, and he moves the scene out of a Hamburg house of the 1660s into a vaulted Gothic chamber with pointed windows. An old bearded man kneels before a flask that blazes like a lamp, his eyes raised. The Revolutionary Players history project notes that the picture found no buyer, was reworked in 1795, and sold only four years after Wright's death.
It is a painting about wonder, and it has one thing backward. Wright's alchemist looks up, to heaven. Brand looked down, into a bucket, and then spent the last years anyone can document writing letters to Hanover asking to be paid.