91 Poison Medicine, Murde , and Mystery

CHAPTER 1 The Story of Mary Ann Cotton COLD, CRUEL, AND PAINFUL, MURDER BY POISON HAS BEEN SEEN THROUGHOUT HISTORY AS A TRULY HORRIBLE CRIME. MORE HORRIBLE YET, IN MARY ANN COTTON'S CASE THE VICTIMS WERE MEMBERS OF HER OWN FAMILY. The background Mary Ann Cotton, a nurse, was born in the north of England in 1832 to a very religious family. In spite of her hard upbringing, Mary was described as a kind and open girl. Victims It is thought that in total Mary Cotton killed 21 people, including her mother, three of her four husbands, a lover, and twelve children. Mary's motives The main reason seems to have been money. All but one of her husbands had taken out insurance policies, and Mary received large payments upon their deaths.

How she kept it all secret In those days, the average rate of death was much higher in England, especially among children, so no one thought the deaths were strange. Also, communication was slow, and Mary moved around to avoid suspicion. How she did it All of Mary's victims apparently died from stomach illnesses, but in fact this condition has very similar symptoms to the deadly poison arsenic. In the 19th century, arsenic was freely available and was often used as a cleaning product. A lucky escape Her third husband James Robinson became suspicious when, after the deaths of their children, she tried to convince him to get life insurance. He threw her out and saved his own life. Brought to justice Eventually, Mary's strange behavior and the death of her fourth husband's son caused suspicion, and the case was investigated. The dead boy was found to have huge quantities of arsenic in his stomach. In 1873 Mary was arrested, put on trial, found guilty of murder, and hanged. Even at the end, she continued to say she was innocent.

CHAPTER 2 The Nature of Poison WHAT IS A POISON AND HOW DOES IT WORK? TAKE A LOOK AT SOME FASCINATING -AND DEADLY— CHEMICAL MIXTURES. A poison can be thought of as any chemical substance that causes a harmful change in the body. Medically, it is hard to define a poison, because any substance introduced in large enough quantities can cause illness, harm bodily functions, or cause death. This difficulty has been understood since ancient times, and the Ancient Greeks even used the same word, pharmakon, for both medicines and poisons. A poison that exists naturally in an insect or animal, and which is often introduced into the victim by biting or stinging, is known as a venom, while one in a plant is generally known as a toxin. Until the advance of the science of chemistry in the 19th century, most poisons used by humans were either venoms or toxins.

Plant poisons Plants cannot move to escape the animals that feed on them, so they have other ways to protect themselves. Many have become toxic as a means of defense. Plant toxins range from those that simply bother the skin to those that cause pain or death when eaten. It is surprising just how many common plants, flowers, and fruits are poisonous. Even fruits that we eat on a daily basis, such as apples, have seeds that contain deadly poisons, though in very small amounts. Interestingly, many plants are also toxic to other plants, so certain plants should not be placed together in a garden. Traditionally, plants have been used as medicines to help people and as poisons to kill them. Some plants can be used as both. The plant wolfsbane, for example, was used as a weapon to poison water and arrows, but was also highly valued by doctors for treating the flu and high blood pressure.

Insects The use of venoms is very common in the insect world, and most people are familiar with the venomous sting of bees or wasps. To people, both stings are painful, but these venoms serve different purposes. Bee venom is used for defense and is designed to cause pain; wasp venom is used to immobilize prey. Frogs There are many types of poisonous frogs. Most produce their venom through their skin and are poisonous to eat or to touch. Many South American tribes have traditionally used the venom of the poison dart frog on their arrows when hunting. Some types of poison dart frog venom contain enough poison to kill ten adult humans. Scientists believe that these frogs do not actually produce their own venom, but take it from ants and other insects that they eat.

Snakes When people talk of poisons, the one animal that usually comes to mind is the snake. Snakes have been feared and admired for thousands of years for their terrible venoms. The venom is usually introduced into the victim through little tubes in the snake's teeth, or fangs, and is mostly used to immobilize the prey. Many snakes have enough venom to kill an adult human easily. Fortunately, snakes are naturally shy and try to stay away from people. But every year tens of thousands of people, as well as many more farm animals, die from snakebites. This has led to serious interest in producing antidotes to snakebites. One antidote against snake venom is to use the venom itself in small amounts to help the body's defense system "learn" about it. The body gradually learns to defend itself.