As Duncan Gow, a poor tailor from Edinburgh, ate his vegetable sandwiches, he didn’t suspect that this would be the last meal of his life. He died three hours and 15 minutes later.
It was 21st April 1845, at 4pm. The 43-year-old tailor was ravenously hungry – no surprise, he hadn’t eaten all day, he’d only had a glass of whisky with a friend, around noon. But Duncan’s children, a 10-year-old son and a 6-year-old daughter, decided to surprise their father by preparing him sandwiches from wild vegetables and herbs. Including from parsley, which their father loved so much that that day he ate an entire bunch. He said it was delicious.
He started to feel poorly about an hour later. He left for town, but along the way he began to stagger more and more, leaning on building walls and lampposts. His friends recalled that the tailor didn’t complain either about pain or about feeling bad; he wasn’t excited or feverish, but pale. Passers-by remembered thinking that they were dealing with a drunk.
Gow sat on some steps, where he was found by policeman James Mitchell, who was asked by an indignant woman to “take the drunk away”. Gow testified that he had lost his vision and couldn’t feel his legs, but he very much wanted to return to his home a kilometre away.
But instead of his house, the tailor ended up at the police station, where he was examined by a police doctor. He would later recall that Gow was fully conscious; he was babbling, but still able to give his address. He had trouble opening his eyes, but he turned his face toward whoever was speaking. And he still responded to tickling of his armpits. And later his pulse and breathing started to slow. Duncan Gow died at a quarter past seven in the evening. Three hours and 15 minutes had passed since he ate the sandwiches. What happened?
It turns out that instead of parsley, the sandwich contained a weed: hemlock (Conium maculatum). Because of its appearance (finely formed leaves, small white flowers, a club-like root), it’s often confused for parsley. It has characteristic stems, dotted with purple spots (some call them “the blood of Socrates”, which we’ll return to later). After crushing, it stinks, with an odour similar to mouse urine.
Hemlock kills because it contains deadly alkaloids that cause weakness, loss of feeling, paralysis and finally death. The victim suffocates. A horse will die after eating two kilograms, a cow after 4.5 kilograms, and for a human – as the example of the Scottish tailor shows – a lot less will do the trick. Hemlock is so poisonous that in Scotland it’s called ‘dead man’s oatmeal’. It’s said that hemlock and cowbane (Cicuta virosa) are the most deadly members of their family.
Why do they kill?
Botanists prefer to say that plants don’t poison you so much as defend themselves. The harmful substances help them survive and prolong the species, protect against parasites and diseases, and frighten off herbivorous animals. Plants have no means of escape, so they burn, wound and can also kill.
“Animals quickly learn what’s harmful for them, and avoid certain plants,” says Gdańsk naturalist Marcin Wilga, who under the pseudonym ‘Borsuk’ (badger) appeared on nature shows for Radio Gdańsk. “Cows won’t go near buttercups or aconites. It’s enough to look at a pasture, especially one where there isn’t a monoculture, meaning various species grow. Sometimes you can see how untouched bunches of plants remain on a meadow, diligently avoided by the herbivores. The animals don’t eat them, either because they don’t taste good – for example, they’re bitter like wormwood – or the animals know they’ll make them sick.
“Interestingly, some species benefit from the poisons. Caterpillars of the spurge hawk-moth feast on poisonous spurges, and become poisonous themselves. That means birds won’t eat them. There are also animals that are immune, who the poison doesn’t affect; for example, deer will happily gorge on the nuts of the European beech, or nibble around the poisonous bark of the yew, and sparrows like to eat its toxic fruits.”
“And people?” I ask.
“People have been learning about the properties of plants for centuries, often by trial and error,” Wilga says.
Death from the garden
In the 1982 Przewodnik do oznaczania krajowych roślin trujących i szkodliwych [Guide to the Markings of Domestic Poisonous and Harmful Plants], Professor Jakub Mowszowicz mentions more than 400 species that can be found in Poland and have poisonous properties. 60 of them are highly toxic. They can grow anywhere, even in a neglected garden. Like the aforementioned hemlock and cowbane.
In Poland, cowbane grows vigorously in areas including Kashubia. “I’ve found patches of this plant by Wysocki Lake,” says Wilga. “Somebody had pulled out a large specimen and discarded it. I saw the bulbous rhizome lying there, and I had heard that it should be empty inside. I had a pen-knife with me, so I cut open the bulb, and inside there really were empty spaces.”
They like marshy ground best. Hemlock prospers in swamps, meadows and along ditches. In appearance it slightly resembles carrots, parsnips or coriander, so people think it’s edible. They never guess that it contains a highly toxic poison. The worst is the root; that’s what produces the most poison, similar to a thick, yellow, foul-smelling juice. Supposedly the root tastes sweet. A piece of it can kill a child, and badly poison an adult. The whole thing can knock over a cow. The poison damages the nervous system. The victim feels a tingling in the mouth and experiences drooling, nausea, vomiting, diarrhoea and seizures, and loses consciousness. It’s believed that poisoning by hemlock or cowbane caused the death in 399 BCE of Socrates, sentenced to death by the Athenian authorities. The philosopher’s student Plato was a witness to his death. Socrates is said to have been given hemlock to drink, after which his guard ordered him to walk around his cell until he felt a heaviness in his legs. When that happened, Socrates lay down. The guard squeezed his feet, but the philosopher had lost feeling in them, though he was still conscious, and issued his last request to his friend Crito. He soon stopped moving and died.
For a long time, experts didn’t believe the philosopher had died peacefully, and believed Plato simply wanted to save his readers a description of the master’s suffering. But the quiet death of Duncan Gow convinced historians that Socrates might have died similarly.
Another highly poisonous plant is jimsonweed (Datura stramonium). The American writer Amy Stewart, in her book Wicked Plants, tells the story of settlers who in the 17th century arrived on the coast of Jamestown Island in the colony of Virginia. They were surprised that such a fertile and perfectly-located land was completely uninhabited by the Indians. The island was beautiful, entirely overgrown with white and purple flowers. Some residents started adding them to the menu. And they dropped like flies. It turned out that the innocent-looking plant caused hallucinations that could last for several days, and in large quantities they killed. Five to 10 seeds was enough to kill a child, and 15-25 for an adult.
Stewart also writes that when the British arrived at Jamestown Island 70 years later to put down one of the first rebellions by the colonists, jimsonweed was added to their food. The soldiers didn’t die, but they went mad for 11 days. One blew on a feather as it floated up into the air, another threw sticks at it, a third sat naked in a corner and made faces, a fourth grabbed his comrades and kissed them.
Death from a vase
Adults usually poison themselves with mushrooms, but the most common victims of poisonous plants are children. Why? The fruits of many plants look very appealing, such as the scarlet balls of the mezereum, with a sweet-tart flavour. Just one or two are enough to kill a child; 10 or 12 will take an adult’s life. The victim feels a tingling on their lips, which then swell up along with the face and larynx. Soon the person begins to bleed, and their heart stops working.
“The plant contains two toxins: daphnine and mezerin,” says Wilga. “Supposedly inn-keepers used to add part of the plant to beer, most likely the fruits, and that gave the drink ‘new properties’. Those who survived later recounted how it was a fantastic feeling.”
Mezereum bushes grow in Poland’s Beskid and Tatra mountains, and in the Oliwa forests. They reach to more than a metre tall and they catch the eye, because they bloom as early as late February. The flowers look like lilacs, and they also smell beautiful, a little like hyacinths.
The fruits of the belladonna, or deadly nightshade (Atropa belladonna) also look tasty. Especially the ripe ones: large, shiny and black. In fact they don’t just tempt people, but animals, too – they were once used to poison wolves, hence their Polish name of werewolf laurel. The whole plant contains toxic atropine, but the worst are the berries. They cause strong stimulation, states of euphoria and hallucinations, and even attacks of madness. Three or four are enough to kill a child, and 10 to 20 an adult male. Atropine severely dilates the pupils. The victim begins to babble, then loses consciousness, and can slip into a coma. In 1880, the American farmer Charles Wilson of Virginia lost three children to belladonna: they died one day after another.
The apparently innocent lily of the valley (Convallaria majalis) can also be a killer. The beautiful smelling flowers, the red berries and even the water from the vase it’s stood in are all toxic. At a certain point, people poisoned by lily of the valley start having trouble distinguishing colours; everything looks yellow to them. The plant produces cardiac glycosides, which disrupt heart function, and in severe cases can even stop it.
Death in the marmalade
When Miss Grosvenor, the hero of Agatha Christie’s A Pocket Full of Rye, went into the office of Mr Fortescue, director of the Consolidated Investments Trust, he was already dying. His face was wracked by convulsions, his body by spasms, and broken babbling came out of his mouth. The businessman was taken to hospital, but couldn’t be saved. He was killed by the common yew. A popular tree in parks, gardens and hedges – and in Great Britain, also in cemeteries.
Yews live for a long time. Unlike their victims. “In Henryków Lubański in Silesia grows Poland’s oldest specimen, estimated to be more than 1300 years old,” says Wilga. “Almost the entire plant is highly toxic, except the outer part of the fruit, known as the aril, which is sweet and a favourite among birds, such as sparrows. The rest contains a compound known as taxine.” Eating a few fruits or a dozen, or a handful of the needle-like leaves, as Mowszowicz writes, “can cause gastrointestinal disorders, slow the pulse and in the worst case can stop the heart.”
Yew is bitter. That’s why Christie’s detectives first rejected the possibility that Mr Fortescue consumed the poison in his tea, because it would be detectable there. The taste of taxine could be neutralized by bitter coffee or sweet marmalade – and that’s exactly where the murderer successfully concealed the yew.
Death in the grain
Bread also used to kill. Or rather the toxic plants that got into the flour.
In the winter of 1691, an unusual event occurred in the previously sleepy little town of Salem in the colony of Massachusetts. According to Rev. John Hale of Beverly, eight girls started to behave strangely: “These Children were bitten and pinched by invisible agents; their arms, necks, and backs turned this way and that way, and returned back again, so as it was impossible for them to do of themselves […].” Doctors were unable to find the causes of this condition, so they decided the girls were the victims of possession. As a result of this diagnosis, 19 Salem residents were accused of witchcraft and sentenced to death by hanging.
But the American town wasn’t the only one. In medieval Europe, it happened more than once that whole villages were struck down by the same mysterious illness – their residents were struck by convulsions and hallucinations; they had the impression that something was crawling over them; they danced in the streets as if possessed, until they finally fell down dead. (The dancing mania that accompanied the disease, also known as St. Anthony’s Fire, most likely caused a feeling that the skin was burning.)
The most likely culprit for all this was an ergot fungus, Claviceps purpurea. It attaches to blossoming grains such as rye and wheat. Ergot likes to become like the grain it’s infected; the contaminated bread becomes poisonous. Cases of ergot poisoning are rare today.
Just like there’s no more drunken bread disease. “It was caused by a widespread plant, common ryegrass,” says Wilga. “It’s a weed that once grew along with the crop. At the moment of harvest, the seeds of the grass got into the grain, just like the ergot, and were ground into flour. Consuming bread with the addition of ground grass caused sleepiness, dizziness, convulsions and even loss of consciousness. It looked a little bit like a person intoxicated with alcohol, thus the name of the disease. Fortunately, cultivation has advanced enough that ryegrass seeds don’t get into the crops anymore.”
Among the 400 toxic species, Mowszowicz also mentions marigolds, viburnum, climatis and poppy seeds. And each of them, in an act of self-defence, can burn, sicken or even kill. But these same plants, in small doses, can heal and protect life. For example, in small doses lily of the valley improves circulation; yew contains substances used in cancer medications; and atropine can be an antidote for pesticides.
Translated by Nathaniel Espino