Dressed to the Strychnines, Act II

**Contains major plot spoilers for The Mysterious Affair at Styles and minor plot spoilers for Bleak House by Charles Dickens and The Moonstone by Wilkie Collins.**​

See the previous post, Dressed to the Strychnines: Act I, for a summary of the creation of Agatha Christie’s first novel, The Mysterious Affair at Styles, as well as a synopsis of the book.  The post you are reading will provide an in-depth description of strychnine poisoning in the context of Christie’s first novel.

The Herb of Death

The description of the agonizing death of Emily Inglethorp concludes:

A final convulsion lifted her head from the bed, until she appeared to rest upon her head and her heels, with her body arched in an extraordinary way.

This characteristic effect immediately led doctors (probably including Lawrence Cavendish, though he was loathe to admit) to suspect strychnine poisoning caused Mrs. Inglethorp’s death.  Strychnine would appear in five of Agatha Christie’s novels and five short stories altogether, dispatching a total of five characters.

Strychnine, Agatha Christie, Poison
Chemical structure of strychnine (Source: National Library of Medicine)

Strychnine is derived from plants in the genus Strychnos, and the compound is an alkaloid without any odor but with a very bitter taste.  Its crystals are long, thin, and colorless, and they are poorly soluble in water. It takes nearly 7 liters of water to dissolve 1 gram, but as a salt its solubility is improved without impacting toxicity.  Historically, the poison was used as a pesticide or to raise blood pressure but was not used medically at the time Styles was written.

Absorption and Metabolism

In the human body, strychnine is absorbed across the small intestine following ingestion.  Its toxic effects are due to its propensity to bind to glycine receptors in the central nervous system (CNS), which prevents the typical intercellular communication in which glycine participates.  In between neurons, the functional cells of the CNS, are small gulfs referred to as synapses, which allow for the transfer of chemical messages (neurotransmitters).  Chemicals released from the tail end (axon) of one neuron travel across the synapse to interact with a second, downstream neuron through specific receptors.  One of these neurotransmitters, glycine, counteracts the effects of acetylcholine, the neurotransmitter released when muscle cells are activated.  Glycine acts like a mute on a trumpet; much greater activation of the upstream neurons by acetylcholine would be needed to stimulate muscle contraction in the presence of glycine.

Strychnine has a greater affinity than naturally produced glycine for the glycine receptor; it is 300% more energetically favorable for strychnine to bind with the glycine receptor compared with a similar amount of glycine.  When strychnine replaces glycine, the muted trumpet referenced above loses its mute and will respond at full strength to the slightest stimulus.  In this case, strychnine is an antagonist of the glycine receptor; it binds to the receptor instead of glycine but induces no response in the cell.  (An agonist is a chemical that would bind instead of the typical chemical that binds to the receptor and induces the typical response.)  Consequently, strychnine poisoning causes an uncontrolled sustaining of muscle contraction.

Action of antagonists and agonists

Deadly Effects

In humans the muscles on the back of the body (dorsal side) tend to be stronger than on the front of the body (ventral side), so strychnine’s ability to prevent the inhibition of muscle contraction results in a violent arching of the back, as described for Emily Inglethorp.   Other muscle spasming patterns may be observed, depending on the location of neurons affected by strychnine.  Because strychnine affects motor neurons, other cells in the CNS would function normally after poisoning, and the victim would be completely conscious and aware during the muscle spasming.

Within 15 to 30 minutes after exposure to strychnine (typically through ingestion via food or drink), the poisoning symptoms begin to manifest as muscle tingling and twitching, which is quickly followed by nausea and vomiting.  The muscle twitching intensifies into violent muscle spasms interrupted by short periods of relaxation. The direct cause of death is often asphyxiation; the violent contraction of the muscles in the chest surrounding the respiratory system suffocates the unfortunate soul.

Effect of strychnine poisoning on the human body

There is no specific antidote for strychnine, but if administered quickly enough, muscle relaxers and anticonvulsant drugs may stave off death.  Modern treatment would consist of diazepam (Valium) and artificial respiration to maintain breathing while minimizing muscle contractions.  Activated charcoal may also be administered by mouth to prevent further absorption through the gastrointestinal tract.  In A is for Arsenic: The Poisons of Agatha Christie, author Kathryn Harkup recounts a presentation at the French Academy of Medicine in 1831, where pharmacist P. F. Touery swallowed 10 times the lethal dose of strychnine mixed with charcoal.  He subsequently developed no symptoms of strychnine poisoning.

Partners in Crime

Another confounding factor in The Mysterious Affair at Styles is the administration of a so-called “narcotic” to Mrs. Inglethorp by Mary Cavendish.  Christie never reveals which specific narcotic was added to Mrs. Inglethorp’s cocoa, but it may very well be morphine as it was given to induce sleep.  

Worth noting in this discussion of Styles is the fact that a common side effect of morphine is constipation, which results from diminishing muscle contractions along the gastrointestinal tract.  This decrease in smooth muscle contractions may delay the transit of foodstuffs from the stomach into the small intestine by up to 12 hours.  Since strychnine is absorbed in the small intestine rather than the stomach, a delay in absorption caused by the morphine in her cocoa would have delayed Mrs. Inglethorp’s symptoms of strychnine poisoning.

The inventor of morphine, Dr. Friedrich Sertuerner, gave it the name morphium after Morpheus, the Greek god of sleep. Morphine is an opioid and is typically used as an analgesic.  It is highly addictive and exerts the same effects as heroin in the body. Because heroin and morphine feature more prominently in other Christie stories, greater detail of their physiological effects will be discussed in future posts.

Potassium bromide was used so frequently as a sedative at the turn of the century that the term “bromide” became synonymous with a dull person or a boring platitude. 

Of course, the ingenious and almost undetected administration of strychnine by the perpetrators was accomplished by simply manipulating the tonics that Mrs. Inglethorp already took on a regular basis.  She was in the habit of taking potassium bromide powders as a sedative and also took a tonic that contained strychnine every night.  In the 1920s, tonics containing small quantities of strychnine were sold over the counter and purported to have stimulative effects, increasing alertness and activity; however, there is no evidence that strychnine acts as a stimulant.  The whole bottle of Mrs. Inglethorp’s tonic would contain a lethal dose of strychnine, but she only took a small amount every night with no ill effects.  The metabolic half-life within the human body is about 10 hours, meaning that the concentration of strychnine present in the body at a specific time will be decreased by 50% when measured at 10 hours afterwards, so there would be no additive effects taking small doses every 24 hours for a typical adult. 

As mentioned previously, strychnine is poorly soluble in water and is consequently used in a salt form, such as strychnine sulfate.  Unlike other molecular compounds, the “bonds” that hold together a salt are ionic charges, rather than shared electrons.  In general, molecules will be prone to form compounds that are in the lowest energy state possible.  In a solution in which a strychnine salt is dissolved in water, the addition of another salt (such as potassium bromide) would cause the dissociation of strychnine from its ionic counterpart to form an insoluble precipitate that would settle at the bottom of the bottle.  It was a simple matter for Evelyn Howard to add one or two of Mrs. Inglethorp’s bromide powders to her strychnine tonic and wait for the unsuspecting victim to take the final draught with a concentrated and lethal dose of strychnine.

Comparison of covalent and ionic bonds
Dispensing; Pharmacy; Agatha Christie
The Art of Dispensing: A Treatise on the Methods and Processes Involved in Compounding Medical Prescriptions

By chance, this final dose was taken on the same night that Mary Cavendish chose to also poison Mrs. Inglethorp with a narcotic, although her motive was not to kill.  The addition of this third chemical compound proved to be a red herring but delayed the effect of the strychnine to confuse the method of murder.  The overall scheme to murder Mrs. Inglethorp with her own “medicine” did involve some scientific understanding, which is explained by the fact that Evelyn Howard’s father was a doctor and she herself seems to be a nurse.  During the denouement, Poirot reads from The Art of Dispensing: A Treatise on the Methods and Processes involved in Compounding Medical Prescriptions, which he states could be found at the hospital dispensary.  This is indeed an important book in the history of pharmacology and was first published in 1888.

A Stylish Success

The Mysterious Affair at Styles was overall well reviewed, but Agatha’s favorite review was from The Pharmaceutic Journal, a scientific journal who praised the accuracy of the chemistry in the story.  The novel is almost a love letter to chemistry, and it is easy to imagine Christie wiling away the hours in her dispensary imaging the plot.  It also marks a welcome progression for the detective novel back in to the scientific method.


The development of the mystery novel at this point in history was brief but had not been marked by great scientific integrity.  The introduction of Inspector Bucket’s deductive powers into Bleak House by Charles Dickens were somewhat diminished by the inclusion of spontaneous combustion as a key plot point, and the use of an opium “experiment” in the conclusion of The Moonstone by Wilkie Collins also left something to be desired with regards to what Poirot calls “order and method.”  The introduction of Sherlock Holmes a few years later by physician and author Arthur Conan Doyle was attended by a “profound knowledge of chemistry” by Holmes, according to his biographer, Dr. John Watson.  Further in the canon, Holmes’s deference to science is somewhat hindered by his creator’s burgeoning interest in spirituality.  Nevertheless, there was an opening for detective novels with accurate and intriguing science that was readily assumed by Christie.

Holmes and Watson; Chemistry; Mystery; Detective
Original illustration of Sherlock Holmes by Sidney Paget

Meanwhile in True Crime...

At one point in history, strychnine was reported to be the third most frequently used poison employed by murderers, behind arsenic and cyanide.  No longer often reported as a cause of death, strychnine poisoning was involved in two noteworthy criminal cases around the time of the publication of Styles.  As noted in the novel, strychnine is extremely bitter and difficult to conceal in food and drink.  The poison can be detected in water in as low as 1 part in 70,000; a fatal dose would need to be diluted in 7 liters of water, rendering this method difficult to execute without raising suspicion.

The Blue Anchor Hotel (Source: ITV)

In 1924, just a few years after the release of the novel, Mrs. Mabel Jones, the wife of a British innkeeper, was convalescing from an unspecified illness in France.  There she met a wireless (telegraph) operator named Jean-Pierre Vaquier, and the two began an affair.  Somewhat romantically, as neither spoke the other’s language, Mabel brought a French/English dictionary along on their assignations to use to communicate.  A short time after Mabel returned to England, Jean-Pierre followed and eventually lodged in the hotel run by Mabel’s husband, Mr. Alfred Jones, the Blue Anchor Hotel in Byfleet, Surrey.  Mabel and Jean-Pierre continued the affair in England.

Alfred Jones took regular doses of bromide powders to counteract the effects of alcohol, which he was prone to abuse.  Alfred’s bromide was kept in a small blue bottle stored in the hotel bar.  One morning, Alfred noted upon preparing a dose of his bromide that the powders were not as fizzy as he was accustomed to seeing them, and when Mabel observed the bottle, there were long crystals mixed in with the usual fine powder.  She tasted the long crystals, which were bitter, and then gave her husband some salt water as an emetic (to stimulate vomiting) and some tea with soda (to calm the stomach).  Despite his wife’s best efforts, Alfred succumbed to the convulsions and died about 90 minutes after taking the tainted bromide.

Jean-Pierre immediately came under suspicion.  Investigators seized the blue bottle, which still contained traces of strychnine despite being cleaned.  Evidence emerged that Jean-Pierre had purchased strychnine for the stated purpose of “wireless experiments” and signed the poison register with a false name.  During his criminal trial, an independent wireless expert testified that there were no known applications of strychnine in wireless communications.  Jean-Pierre was found guilty and hanged for the murder of his lover’s husband; the ghost of Alfred Jones is said to haunt the Blue Anchor Hotel to this day.

Another case of murder involving strychnine from several years prior to the publication of Styles was Dr. Thomas Neill Cream (The Lambeth Poisoner), who murdered four women in 1892.  As a young doctor in Canada, Dr. Cream had a practice in which he regularly performed abortions until the dead body of a young chambermaid was found in his office, and he fled to Chicago.

After resuming his work as a physician in the United States, another young woman associated with Dr. Cream died.  He was arrested under suspicion for her murder but was ultimately not charged.  Dr. Cream was found guilty of murder the following year after he poisoned the husband of one of his patients with strychnine.  Although given a life sentence, Dr. Cream was released 10 years later due to “good behavior.”  Dr. Cream traveled to England upon his release.

Soon after arriving in London, Dr. Cream began poisoning sex workers by administering pills that he stated would improve the women’s complexions.  The pills, however, were composed primarily of strychnine, and the consumers would perish in agony several hours later. In short order, Dr. Cream was arrested and rapidly convicted, then hanged at Newgate Prison.  A perhaps apocryphal story asserts that his last words were “I am Jack the…,” with the hangman’s noose pulling taut prior to completion of the sentence.  Dr. Cream was imprisoned in the US in 1888, during Jack the Ripper’s murderous spree in Whitechapel, so it is not likely that he was the perpetrator. 

The next blog post—Dressed to the Strychnines, Act III—contains a historical examination of double jeopardy in England as it pertains to The Mysterious Affair at Styles.

What’s in a Dame?

Welcome to Christie’s Mysteries.  This blog is an in-depth exploration of the world of Agatha Christie—not only her classic and lesser known stories but also contemporary happenings in the realm of true crime, early forensics, and the life of the Queen of Mystery herself.  It is 2018, and one may question why one would start a blog devoted to Agatha Christie.

Despite the very recognizable anchorings of Christie’s stories in a particular epoch—an art deco salon with a stout Belgian dandy, a Middle Eastern archaeological dig with a stereotypical British patriarch, a quaint country village with an elderly spinster busybody too clever by half—there is something timeless about Christie’s work.  Perhaps it is the deliberate laying out of a complicated mystery populated by interrelated and familiar suspects with a typical denouement gathering all the suspects in a single room for the solution of the mystery, tying up any and all loose ends.  In the world of true crime, this type of resolution is elusive at best but more often completely unrealistic.  But how comforting it is to read a story by Christie knowing that no matter how complex and insoluble the crime seems, by the end of the book it will all be wrapped up neatly.

Dawn of the Dame

Agatha Mary Clarissa Miller was born the third child to an English mother and American father in the seaside village of Torquay on September 15, 1890.  Her nearest sibling, a brother, was 10 years her elder.  Prior to Agatha’s birth, the family of 4 (with an older daughter to round them out) were vacationing in Torquay when Agatha’s father was summoned to New York for business.  He provided his wife some money to rent furnished lodgings in Torquay for a year or two, given that the family ultimately wanted to settle down in America.  Together with money she had from her father-in-law, Agatha’s mother Clarissa purchased a house called “Ashfield”—decidedly not a vacation rental but rather a home to raise a growing family in the picturesque resort town.

Youth, Writer, Mystery
Young Agatha, year unknown

Torquay was long considered a health resort, where wealthy visitors would convalesce.  In 1902, the first advertising campaign to attract healthy tourists to Torquay was launched.  There was a steady influx until the start of World War I, during which time Torquay welcomed recovering servicemen.

The older Miller siblings attended boarding school, and Agatha had free reign over the house and grounds, including a full library.  She had no formal education and taught herself to read at the age of 4.  Agatha’s mother elected to home school her and educated the future writer herself with help from governesses and grandmothers.  The Miller family was middle class and therefore staffed only female servants, as butlers and manservants were reserved for wealthier families.  Accordingly, strong female figures were present in Agatha’s life from an early age, and Agatha (along with her siblings and mother) shared a belief in her mother’s own clairvoyance, stating of her mother years later, she was “always slightly at variance with reality.”  When Agatha’s siblings were home from school, they would entertain her in ways that would subsequently inform her writing style and plotlines.  Older sister Madge would play a game called “The Elder Sister,” in which she would portray a devious and deceptive older sister.  Agatha’s brother Monty was athletic and a bit of a showman and took Agatha out on his boat around Torquay only once, impatient with her seasickness.  Agatha’s father, although often absent during her childhood, produced amateur theatricals in Torquay, and Agatha was involved in her own amateur plays throughout her youth.

The House of Lurking Death

Although her upbringing was comfortable and may be called idyllic, Agatha experienced some early-life incidents that likely influenced her writing through her final novel.  In her younger days, Agatha had a dream that an 18th-century musketeer called the “gunman” could replace members of her family without detection.  In addition to this dark nightmare, several traumatic events occurred during Agatha’s formative years.  Young Agatha witnessed one of her beloved pet dogs being run over by a horse-drawn carriage and on a separate occasion was chased off her neighbor’s property by man who threatened to boil her and her nanny alive.  Agatha later said of the latter, “From that day to this I have never known so real a terror.”  She was 4 years old.

When she was 11, Agatha’s father perished from pneumonia, and the family found itself in less than comfortable financial conditions.  Agatha and her mother became closer and rented out Ashfield to spend a couple years in Paris, where Agatha became fluent in French and attended finishing school.  When the two Miller women returned to England, Clarissa arranged for Agatha’s formal coming out in Cairo in 1907.  This location and the field of archaeology would feature prominently in Agatha’s future life and writing, but her time in Egypt at this juncture was spent cavorting with military officers rather than examining antiquities.  She found most of her suitors lacking until she met a handsome officer after her return to Torquay, Lieutenant Archibald Christie, who was anticipating entry into the Royal Flying Corps.  A few days after Agatha and Archibald danced at a ball on January 2nd, 1912, Archie dashed up to Ashfield on his motor bike to officially begin their courtship.

Mosques in the Sharia Bab-El-Wazir, Cairo

The Secret Matrimony

The First Battle of the Marne from September 6th through 10th, 1914, staved off the advancement of German troops into France and notably introduced the use of trench warfare, a defining element of the Great War.

Although the couple intended to marry, Clarissa Miller insisted that the couple postpone their wedding until Archie earned an adequate salary to support himself and Agatha.  Archie continued his military training for the next 18 months and traveled to France to fight in the battles of the Marne and Aisne in August 1914.  During their time apart, Agatha served as a practical nurse for the Voluntary Aid Detachment at the Red Cross Hospital in Torquay.  Shortly after Archie returned on leave, the two married in secret on December 24th, 1914, in a small ceremony witnessed by Archie’s stepfather and a total stranger.  Two days later, on Boxing Day, Archie departed from London for another 6‑month separation.

Agatha Takes a Job

Beginning the next year, Agatha took a new assignment with the Voluntary Aid Department in the Dispensary at Castle Chambers.  With extra time on her hands, Agatha began writing mystery fiction in addition to studying for the Society of Apothecaries examination.  Agatha’s knowledge of poisons was largely informed by her time at the dispensary, and she would ultimately use poisoning as a means of dispatch in about half of her novels, including her first.  Her older sister Madge had challenged Agatha to write a detective story, and she completed The Mysterious Affair at Styles during a 2-week stay at the Moorland Hotel on Dartmoor.  The novel was turned down by the first three publishers to whom Agatha sent her manuscript.  Agatha sent it to a fourth, The Bodley Head, but had not received a response by the time Archie returned to London later in 1918.

Christie volunteered as a nurse and dispenser during World War I

After the end of World War I, Agatha and Archie established their home in London, and Agatha gave birth to their first child, Rosalind, on August 5th, 1919, in her childhood home of Ashfield.  Around this time, John Lane of The Bodley Head informed Agatha that his house would publish, and the world was introduced to Agatha Christie and Hercule Poirot in 1920.

The Worshipful Society of Apothecaries of London, still in service today, was recognized by royal charter in 1617.  Its Grant of Arms includes Apollo, the Greek god of healing, killing the dragon of disease and supported by 2 unicorns, which were part of King James’s royal arms.  The society’s motto is “I am spoken of all over the world as one who brings help” (from Ovid’s Metamorphoses).

A subsequent blog post in three acts (Dressed to the Strychnines) will delve into The Mysterious Affair of Styles—its genesis and the creation of Poirot as well as an examination of the various poisons employed and the unique legal history of double jeopardy.