Valentin Rose

Unfortunately, no images of Valentin Rose exist

Valentin Rose (1761-1807) is an obscure figure in the history of toxicology and arsenic. Despite developing the first reliable test for detecting arsenic in tissue, he is almost entirely absent from the history books.

What we do know…and it’s not much

Rose was a German pharmacologist from Berlin who received his education in Frankfurt (from 1778-1782). Upon returning to Berlin, he worked in his father’s pharmacy, which he became provisor for in 1785, after his father’s death, and gained ownership of in 1791. He was active in the lecture scene and was co-editor of Berlinisches Jahrbuch für die Pharmacie und für die damit verhundenen Wissenschaften, with Adolf Ferdinand Gehlen.

He is credited with the discovery of sodium bicarbonate in 1801, and inulin in 1807 (a naturally occurring polysaccharide found in many plants).

It is likely that Rose’s route to discovery began the same way as his (later) English counterpart, James Marsh (who developed the Marsh Test for arsenic). It was participation in a murder trial that inspired both men to search for a method of detecting arsenic in tissue. For Marsh it was the murder of George Bodle; for Rose it was the trial of Sophie Ursinus in 1803.

The Case

Sophie Ursinus was the widow of a Prussian privy counsellor. She was arrested in 1803 for the attempted murder of a male servant with whom she had quarrelled. Suspecting what his employer had been done, he took the plums Sophie had given him to a chemist. The plums were tested and arsenic was found.

Her arrest for attempted murder set tongues wagging. Had this been her first foray into arsenic? Or had there been others? Her lover had died in 1797, her husband in 1800, and her aunt in 1801. Upon her aunt’s death, Sophie inherited a fortune.

Rumours led to action and Dr. Georg Welper, medical inspector for Berlin, ordered the exhumation of the husband and aunt. After an investigation, it was determined that consumption (the original cause of death for the lover) was accurate, so he was left in the ground. To prove murder, they first had to find arsenic in her potential prior victims. That task fell upon chemist Martin Heinrich Klaproth and his assistant, Valentin Rose. (Unlike Marsh who performed the experiments himself, Rose did not lead the tests done in the Ursinus case.)

The remains of both husband and aunt were intact enough to allow for the tissue to be examined. During both autopsies, parts of the digestive tract showed redness and inflammation that is indicative of contact with an irritant poison. Unfortunately, in the husband’s case, no arsenic could be detected. Klaproth and Rose deferred to the original attending physicians that death had been from natural causes. Such was not so for the aunt. They believed her to have been poisoned and Sophie was sent to trial for murder.

The evidence against Frau Ursinus guaranteed a conviction for the attempted murder, and provided circumstantial evidence for the murder of her aunt. She had purchased arsenic on the pretense of killing rats (there were none reported in the house), and it had been found in the plums she had given the servant. Sophie confessed to the attempted murder and at her trial in September of 1803 she was found guilty of the murder of her aunt. She was sentenced to life in prison.

The inability to determine if arsenic was present in tissue set Rose to work, intent upon resolving the problem. Three years later, he met with success.

The Test

The test, in itself, is rather simple (from a nineteenth-century chemist’s perspective if not from ours). In 1806, Rose obtained the stomach of a man known to have died of arsenic. He cut it up and boiled the pieces in distilled water. He filtered the mixture (or “soup” as Linda Stratmann refers to it) and removed all traces of organic matter using nitric acid. From the remaining liquid, Rose produced a precipitate, then used Metzger’s method to test for arsenic. The results confirmed the presence of arsenic when “mirrors” of metallic arsenic appeared.

(Chemist Johann Daniel Metzger discovered that, when a compound of arsenic was heated in a test tube using a charcoal fire, dark shiny deposits of metallic arsenic formed on the cooler parts of the glass. Because of their shiny, reflective appearance, these deposits were referred to as “mirrors” of arsenic).

The Rose Test put to trial (pun intended)

In 1809, Anna Margaretha Zwanziger was arrested on suspicion of murdering a number of people. Zwanziger was a Bavarian housekeeper who had gotten into the habit of poisoning individuals with whom she’d quarrelled, as well as wives whose husbands she coveted. In addition to murder, she was believed to have repeatedly administered small doses of arsenic to her employers to make them sick so she could nurse them back to health.

She was caught during an attempt at mass murder. When her employer dismissed her from service, Zwanziger carried an act of spite. She gave the other servants poisoned drinks. Though the adults recovered, a child didn’t. When the incident was investigated, the finger was pointed at Anna. She had recently refilled the salt barrel, though it was not her responsibility to do so. The salt was tested and arsenic was found.

This prompted the exhumation of three individuals (five, six, and fourteen months in the ground). More victims were suspected, but only three were tested.

The Rose test was performed on each of them and arsenic was found.

Zwanziger confessed to the murders, and on September 17, 1811, she was beheaded with a sword.

Why is Rose absent from the history books?

Rose published his test in scientific journals, and, as evidenced by the Zwanziger trial, it was known in German-speaking regions. Why was it not known elsewhere?

The spread of scientific information depended upon it being published (which Rose’s was), the distribution of the journal (geographical and quantities purchased), and whether or not it was available in translation. Awareness of the test reached France and Mathieu Orfila (the father of toxicology), but there doesn’t seem to have been much attention given it in his circles. It reached England in Orfila’s Treatise on Poisons was published in England in 1816, but his mention of Rose’s test did not garner much attention. It is unlikely that his Treatise would have reached areas such as Woolwich where James Marsh worked, and where he devised his test.

When James Marsh published details of his test in 1836, it was touted as the breaking of a barrier—the triumph of science to (finally) extract arsenic from human flesh. This resulted in greater accolades and more publicity. Because of that, the significant accomplishment of Valentin Rose fell into obscurity.

Bibliography

• Stratmann, Linda. The Secret Poisoner: A Century of Murder. (New Haven, Connecticut: Yale University Press, 2016).