Date of birth: 2 September 1794
Date of death: 21 June 1846
James Marsh (Chemist), a British chemist who created the Marsh test for detecting arsenic, lived from September 2, 1794, to June 21, 1846. Before joining the Royal Artillery, he worked as a laborer in Woolwich during the late 1810s and early 1820s. He married Mary and they had four children, two of them died as infants. Lavinia Bithiah (1821-1896) and Lucretia Victoria (1821-1896) were his surviving daughters (1829-1910).
Poison has been used as a murder weapon for thousands of years. In the United States, however, forensic toxicology has only lately become an important tool in criminal investigations and court cases. There are more historical events that increased scientific understanding of poison and helped develop the field of forensic science by exploring some of the milestones of forensic toxicology in America.
Sir Edward Bulwer-Lytton, a British Member of Parliament, released Lucretia—or the Children of the Night, a three-volume book, in December 1846. Bulwer-Lytton was a prolific writer of the day, and his work includes the famous opening line, “It was a dark and stormy night.” To quote the author, the book is a “dark and stormy tale” in which blood “gushes and plashes” as the heroine, Lucretia Clavering, poisons her way from one sensation to the next. Her first name was Lucretia Borgia, one of history’s most famous poisoners, and her surname was derived from an Essex village that had lately been in the headlines as a hotbed of criminal poisoning.
Lucretia became a best-seller almost immediately, but not everyone was impressed. It was called “hateful from the first page to the last” by the Daily News, and “a disgrace to the writer, a shame to us all” by The New York Times. The attacks in the popular press were predictable enough, given the subject matter and Bulwer-lucid Lytton’s style, but the usually sober London Medical Gazette, edited by the seriously scientific Dr. Alfred Swaine Taylor, Professor of Medical Jurisprudence at Guy’s Hospital in London, UK, sounded equally overwrought. The publication said that Lucretia was written specifically for the goal of “lending dignity to the crime of assassination,” and that the most eloquent novelist of the day had given the world a work of fiction. “the entire plot details and moral of which form a most complete revelation of the art of murder by poison”.
It was significant that the Gazette chose to discuss Lucretia at all. “Clinical Observations on Diseases of the Genito Urinary Organs” and “On Gout: Its History, Causes, and Cure” were two recent titles that sat ill with the journal’s customary selection of materials for review. The period of Lucretia’s release in 1846 coincided with a poison scare that lasted at least 20 years in the British public.
Bulwer-Lytton claimed in his story that a colorless, tasteless liquid has “hitherto baffled every known and positive test in the posthumous inspection of doctors.” In Britain, no such poison was known, but arsenic given in subacute dosages over time came close. Arsenic is a metallic element that can travel through the human body safely if it is kept in its elemental state. Most people refer to arsenic trioxide or white arsenic as it was known in the nineteenth century when they simply say arsenic. White arsenic is a tasteless, seemingly harmless powder that, in small amounts, can be lethal.
White arsenic was sold over the counter at druggist stores for a few pence and with few questions asked throughout the first half of the nineteenth century. Poisoning cases were notorious for being difficult to diagnose. The basic symptoms of arsenic poisoning—vomiting and diarrhea—are similar to numerous stomach disorders that were widespread in the nineteenth century, but doctors only had those symptoms and the circumstances in which the patient became ill to go on at the time.
James Marsh (1794–1846) is historically well-known for his study and development of a trustworthy, easy laboratory test for the identification of minute levels of arsenic during his remarkable career as an English chemist in the 1830s and 1840s. The Marsh test (or Marsh Arsenic test), as it is now known, included forensic toxicologists examining supplied samples of food, liquids, or deceased human tissue from the middle of the nineteenth century to well into the twentieth century. Mathieu Joseph Bonaventure Orfila (1787–1853), who is widely regarded as the father of forensic toxicology, frequently employed the test.
The Marsh test provided experts with a quick and precise means to identify minute levels of arsenic, a chemical pollutant that can be lethal when unintentionally or purposely introduced into the body. Arsenic poisoning was a major concern in Marsh’s day all over the world, and it was frequently undetected by routine testing. Marsh’s invention of this testing procedure and its accompanying apparatus aided in the scientific improvement of poisoning investigations as well as the outcome of several prominent murder convictions.
Marsh grew up in England and began his professional career at the Royal British Arsenal (commonly known as the Woolwich Arsenal), which was located in the town of Woolwich east of London. His scientific abilities were likely first discovered in 1836 when leaders of the neighboring town of Plumstead sought his guidance on the cause of arsenic poisoning in the body of a local leader who had died. Marsh, a competent chemist who was familiar with approved German autopsy protocols, applied yellow precipitates, ammonia solvents, and other laboratory reagents to the deceased body’s tissues and the coffee that was believed to contain the poison.
Marsh submitted his findings during the inquest, which revealed that the victim’s corpse contained arsenic. However, the jury misunderstood his technical testimony during the trial and acquitted the decedent’s alleged grandson. (After being convicted of other crimes, the grandson confessed to the crime.) Marsh is now regarded as the first person to present the results of toxicology analysis in court as a result of this effort.
Marsh became resolved to develop new laboratory tests that might establish the existence of even minute quantities of arsenic and make the results understandable to even the most uneducated people after trying to persuade the jury.
Marsh generated hydrogen by a reaction of adding solid zinc metal to a glass receptacle containing either hydrochloric acid or sulfuric acid, based on previous work (of changing arsenic to a similar gas called arsine) by Swedish scientist Karl Wilhelm Scheele (1742–1786). Marsh may generate hydrogen gas by adding tissue or body fluid to the hydrogen-generating container, which would react with zinc and acid to produce hydrogen gas. If any form of arsenic was present, Marsh heated the hydrogen gas to produce arsine gas, which fumed off to deposit a silvery-black layer on a porcelain bowl, indicating metallic arsenic.
Even when just trace levels of arsenic were present, Marsh was able to induce visible stains on the bowl. Marsh’s technique was able to identify arsenic concentrations as low as 0.1 milligrams (0.0000035 ounces). Marsh later devised a U-shaped glass tube with a narrower nozzle at one end to allow for a controlled reaction and to aid in the ignition of the outgoing gas. Marsh published a paper in the Edinburgh Philosophical Journal in October 1836 based on his pioneering research and subsequent test, followed by two more Marsh test articles in 1837 and 1840.
Toxicologists and other experts from all around the world explored Marsh’s information after it was published. Orfila, a French toxicologist who was already well-known in his own right, improved the Marsh test by advising that all reacting chemicals be verified to be arsenic-free before being employed in an investigation. The Marsh test was crucial in securing a conviction in a significant murder case in 1840, one that was resolved by an Orfila report. Orfila used the Marsh test to resolve the controversial trial of Marie Lafarge, who was charged with murder in her husband’s arsenic poisoning. Lafarge was found guilty and put to death based on his findings (which were later reduced to life in prison). Due to the scientific work of Orfila and his expert application of the Marsh test, procedures were first formalized for proving poisoning in court cases with the use of toxicological analysis.
Marsh spent most of his career at the Woolwich Arsenal, working in the disciplines of electromagnetic and artillery technology. March died in London at the age of 51 while still working at the arsenal. The Marsh test was widely used by forensic toxicologists after his death until it was replaced in the latter part of the twentieth century by more technically sophisticated methods of instrumental analysis such as atomic absorption spectroscopy and x-ray fluorescence spectroscopy.
The Marsh test is a highly sensitive method for detecting arsenic, and it’s especially valuable in forensic toxicology when arsenic has been used as a toxin.
In Bill Bergson Lives Dangerously, the Marsh test is performed to prove that particular chocolate is poisoned with arsenic.
Bunter, Lord Peter Wimsey’s manservant, utilizes Marsh’s test from Strong Poison to prove that the perpetrator was in fact in possession of arsenic.
Flavia de Luce, a 12-year-old sleuth and chemistry genius, utilizes the Marsh test to determine that arsenic was the murderer’s weapon in Alan Bradley’s As Chimney Sweepers Come To Dust.