Dorothy Hodgkin
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Library of Congress Cataloging-in-Publication Data
Names: Thiel, Kristin.
Title: Dorothy Hodgkin: biochemist and developer of protein crystallography / Kristin Thiel.
Description: New York : Cavendish Square, 2017.
| Series: Women in science | Includes index.
Identifiers: ISBN 9781502623133 (library bound) | ISBN 9781502623140 (ebook)
Subjects: LCSH: Hodgkin, Dorothy, 1910-1994--Juvenile literature. | Crystallographers--Great Britain--Biography--Juvenile literature. | Scientists--Great Britain--Biography--Juvenile literature.
Classification: LCC QD903.6.H63 T45 2017 | DDC 548’.09--dc23
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Printed in the United States of America
CONTENTS
Introduction: A Major Presence in the Study of Tiny Matter
ONE From Classroom to Laboratory: Always Dorothy
TWO A Lab of Her Own
THREE Where There’s a Crystal, There’s a Structure; Where’s There’s a Structure, There’s Understanding
FOUR Obstacle Courses and Support Systems
FIVE From Google Doodle to Rural Diamond
Chronology
Glossary
Further Information
Bibliography
Index
About the Author
The lab was Dorothy Hodgkin’s home away from home.
INTRODUCTION
A MAJOR PRESENCE IN THE STUDY OF TINY MATTER
In 1964, not even four out of every one hundred women had completed four years of college. About seven out of one hundred people working in science, technology, engineering, and mathematics were women. That year, Dorothy Crowfoot Hodgkin won the Nobel Prize in Chemistry for her work in crystallography. The Nobel Prize is considered one of the world’s highest achievement awards in chemistry. Hodgkin was the third woman to win the Nobel Prize in Chemistry and remains one of only four women ever to win it.
WHAT IS CRYSTALLOGRAPHY?
Hodgkin used crystallography as a chemist. Crystallography is the study of the atomic structures and molecular structures of everything from proteins and viruses to glass and fiber—and even gases. It is the study of a thing’s basic, foundational makeup. It is cross-disciplinary, meaning many fields of study use it. Chemistry, geology, biology, and physics are some of those fields that benefit from crystallography’s approach.
Hodgkin was a leader in the technique of X-ray crystallography, which uses beams of strong, invisible light to see inside things. Because of the advances she and other scientists made in crystallography, today we are able to learn much more, much faster, than we could before.
Crystallography has an interesting history when it comes to women. Traditionally, and still today, there are more men than women studying and being recognized for their work in the sciences. The science of crystallography, a branch of natural science, has been no exception. But it has seemed to attract and encourage more women than other physical sciences. Hodgkin was but one pioneering female crystallographer.
By knowing what something is made of—its atomic structure—we learn how it functions. Knowing how something operates allows us to work with it. The pharmaceutical and biochemical fields rely a lot on crystallography to understand diseases and cells and then to make better medicines. Hodgkin contributed to health by determining what makes up penicillin, insulin, and vitamin B12.
WHO WAS DOROTHY HODGKIN?
Born in 1910 in Egypt to British parents, Dorothy Hodgkin attended school in England. She studied chemistry from a very young age, and as she grew up, she never wavered in her commitment to science, even when she married. In fact, she earned her doctorate, the highest degree possible in her field, in 1937, the same year she married. Her career began as her family did. Most of her important work in chemistry happened as she raised three children.
Hodgkin is most known for being a groundbreaking scientist, but she was also passionate about promoting world peace and safety for scientists doing work in dangerous places. For more than a decade, she led the Pugwash movement, which was concerned with people using scientific research for good purposes, to help everyone rather than hurt anyone.
Hodgkin died in 1994, but her discoveries remain useful today, and people still work toward her social values. Many of the students she taught went on to make their own important discoveries, and many more use the technique she helped to develop. One hundred years after her birth, fifty-six thousand atomic structures had been calculated using crystallography.
Other discoveries, some beyond our imagination, are sure to follow. Hodgkin herself suggested that one of the most important things her work offered
was possibility. X-ray crystallography can answer questions we know we have and questions we haven’t even thought of yet. In her Nobel Prize lecture, she said, “A great advantage of X-ray analysis ... is its power to show some totally unexpected and surprising structure with ... complete certainty.”
London, the United Kingdom’s capital and its most populated city, has always bustled with activity, even before multilane roads, skyscrapers, and power lunches. This photo was taken in 1922, when Hodgkin was twelve years old.
CHAPTER
ONE
FROM CLASSROOM TO LABORATORY: ALWAYS DOROTHY
Dorothy Hodgkin lived at a time when it was not common for women to be scientists, or to have much of an education at all. However, during her life she not only excelled at school but also went on to complete her PhD, or doctorate. Though she earned the right to shout her qualifications from the mountaintop, she did not. For the most part, she was a simple, humble person. She asked even her newest and youngest coworkers to call her by her first name.
STARK DIFFERENCES IN CHILDHOODS
When she went into labor with Dorothy, her first child, on May 12, 1910, Grace (known as Molly) Crowfoot was far from her home country of England. She was in Cairo, Egypt, because her husband, John Crowfoot, worked for the Egyptian Education Service. Grace’s work was also focused in the Middle East and northern Africa. She was an authority in early weaving techniques and was a botanical artist—she drew the plants of the region. When they lived in Sudan, young Dorothy often would walk with her mother to collect flowers.
Hodgkin, the Crowfoots’ firstborn, grew up in a special situation. Her parents were educated and had good jobs that allowed the family to live in interesting places and learn a lot. In addition to her own intelligence and determination, Hodgkin could credit her parents and sheer good luck for helping her rise to greatness in science, humanitarian work, and family life.
Many other people at that time faced work and life challenges. Even for boys and men, the world in the early to mid-1900s could be a difficult place. In the United States, child labor wasn’t made illegal until 1938. Work was difficult, tiring, and often dangerous. The 1911 Triangle Shirtwaist Factory Fire was a terrifying example of what could go wrong in modern industrial society. People received low wages for working long hours in the unsanitary and dangerous Triangle Shirtwaist Factory. When a fire broke out, many workers could not escape because the exits were locked, the fire escapes could not support the weight of the people, and the firefighters’ ladders and hoses could not reach high enough. Most of the 146 people who died were in their teens or twenties, some as young as fourteen years old.
In 1917, the United States entered World War I, and the Selective Service Act, passed on May 18, 1917, introduced the draft. This meant the military could order men between the ages of twenty and thirty to join the military and go to war. Also at this time in the United States, there was great racial injustice and unrest. Lynchings were legal, race riots happened with some frequency, and the Ku Klux Klan operated in most of the states.
For everyone, education was a luxury. In 1910, there were as many people twenty-five years or older who had less than an eighthgrade education as there were people with more than an eighth-grade education. Fewer than four out of every one hundred women had completed four years of college. Almost one-third (30.5 percent) of those identifying as “black and other” in the US Census were illiterate, unable to read or write in any language. Five percent of whites were illiterate.
Hodgkin had a different experience. Her science education began around age ten, when her mother took her to an exhibition on geology at Gordon College in Sudan, where guides instructed on panning for gold. Excited by this idea of studying rocks and dirt, young Hodgkin repurposed a dish from her parents’ kitchen to do her own sifting through sand, dirt, and rock in the stream that ran through her backyard. While many children may have stopped at that point, Hodgkin took her finds back to the college. She had a hypothesis about what she’d found, and she wanted to run tests to confirm this educated guess. What she found surprised her: ilmenite. This mineral made of iron and titanium wasn’t mentioned in her textbooks. (It is found on the moon! And, interestingly, geology also studies the rocks of other places like the moon.) Fortunately, the Sudanese government’s chemist, A. F. Joseph, was also a family friend. He helped her solve that puzzle and set up her own home laboratory. She bought glass tubes and crystals from the chemist. Later, when interviewed for the story preservation website Web of Stories, Hodgkin would laugh when she remembered how funny it was that he “didn’t seem to have any particular rules about what he shouldn’t ... allow ten-year-old children to have.”
SCHOOL DAYS
When World War I broke out, Molly Crowfoot took her four daughters to England for safety. She didn’t stay long. Work—hers and her husbands— called from Africa. The family would reunite in England only a few months every year. At that time, it was not uncommon for families who worked in jobs like the Crowfoots’ to live in separate countries.
Now living across the world from her parents, young Dorothy Hodgkin continued to excel in science, conducting exciting experiments. She was one of two girls allowed to join the boys in chemistry class— which was taught by a woman. “If a girl was going to a university, or hoped to go to a university, she could do chemistry, and I think that I know several girls who were persuaded by [that teacher] to do chemistry,” Hodgkin said in a Web of Stories interview decades later. In one lesson, the students mixed a solution of alum and copper sulfate. Crystals grew from the solution over the next few days. This was Hodgkin’s first exposure to what she’d learn was crystallography. That type of science gathers data from a pure form of a substance, a crystal. Crystals are often thought of as jewels or as beautiful stones found in caves. But many substances can be crystallized. You can grow crystals of a substance. In a crystallized sample of a substance, all the molecules are arranged in a regular, orderly pattern across all three dimensions.
COLLEGE DAYS
Before Hodgkin’s college classes started, she went on an archaeological dig with her parents at Jerash, in Jordan. After working for the education service, her father became the director of education and antiquities in Sudan, which is the country immediately to the south of Egypt, and then the director of the British School of Archaeology in Jerusalem, Israel. He led several archaeological digs in the Middle East. His oldest daughter’s job was to record the patterns of the mosaics on the remains of more than a dozen fifth- and sixth-century Byzantine churches that they uncovered, in order to help them learn about the people who used to live there. She never wavered from her commitment to science, but as she worked alongside her parents to excavate the site, she realized she wasn’t sure which science she wished to study.
A KIDS’ BOOK MAKES AN IMPRESSION
When Hodgkin won the Nobel Prize for Chemistry in 1964, she had been in her profession for about thirty years. During her career, she had studied and worked with a lot of important people, but the person she named in the first sentence of her Nobel Lecture, W. H. Bragg, was an influence from her childhood.
Bragg also won a Nobel Prize, in 1915. Even though he won in physics, not in chemistry, his work was similar to Hodgkin’s. He won the award for using X-rays to analyze the structures of things. Hodgkin’s mother gave her Bragg’s children’s book, Concerning the Nature of Things (1925), when Hodgkin was fifteen. This book told its young audience about scientists using X-rays to “see” inside things, to see their atomic structures. Hodgkin said in her Nobel Prize lecture that she first learned about X-rays and structures from that book.
With detailed paintings, Hodgkin recorded the mosaics uncovered during her and her parents’ time in Jerash, Jordan.
Hodgkin started studying archaeology and chemistry in 1928, her first year at Somerville College, one of the women’s colleges at Oxford University. Oxford is made up of colleges; when you attend Oxford, you are a student of both Oxford and a particular college. Those col
leges used to be single-sex, some admitting only women and some only men. Hodgkin analyzed glass tiles, also called tesserae, from the Jerash site with E. G. J. Hartley, an Oxford chemist. She told her parents about it in a letter in 1929. She was most excited about finding a small, or trace, amount of titanium in the blue glass. Finding the metal reminded her of one of her first experiments back when she was about fourteen. Together with Dr. Joseph in Sudan, she had tested for titanium and found it. She had kept her notes, and they’d proven useful to her as an adult.
As part of her chemistry degree, she took a course in crystallography. Impressed with her work, her tutor, F. M. Brewer, suggested she do research using X-ray crystallography. Now Hodgkin wouldn’t be growing crystals and laboriously trying to study through experimentation what was happening in them. She’d be seeing inside them with X-ray technology.
When you think of X-rays, you probably think of being able to see inside the body. That is what Hodgkin was going to do: see inside crystallized versions of substances by using X-rays.
Her first project was thallium dialkyl halides with H. M. Powell, another chemist working out of the university. Hodgkin was happy with the strong crystals she grew and her drawings of them, even though their equipment led to some blurry photographs. Step by step, she progressed toward her ultimate field of work.
One of her favorite visiting lecturers at Oxford, a man by the name of J. D. Bernal, taught regularly at Cambridge, and Dorothy Crowfoot had her eye on working with him. It didn’t hurt that she was fed up with Oxford’s equipment. She reminisced later, laughing, that the X-ray tube at Oxford was so moody—sometimes working and sometimes not—that she might as well see another lab. Dr. Joseph, her childhood neighbor and the man who’d helped her with her first lab, played a role in introducing her and Bernal. Hodgkin soon went to Cambridge and found herself studying with Bernal, whose work on sterols she thought “very revolutionary.” Bernal also immediately appreciated Hodgkin’s natural way with X-ray crystallography, including her ease making thousands of complex mathematical calculations to create a Patterson map, a contour map that could be used to define the distances between atoms in a crystal. Along with working together, the two formed a brief romantic relationship, although it would end amicably several years later.