Edith Clarke was the world's first female electrical engineer. She later became the first female Professor of Electrical Engineering at the University of Texas in Austin.
Edith specialized in electrical power system analysis and later wrote the seminal book Circuit Analysis of A-C Power Systems.
Born in February of 1883 she would lead a stellar career breaking many firsts for women the electrical engineering community.
She died in October of 1959. Today she is still as highly respected posthumously as she was in life.
Edith Clarke's Early Life and Education
Edith Clarke was born in on February 10th, 1883 in the small farming community of Ellicott City, Howard County in Maryland. She was one of nine children to her father John Ridgely Clarke and mother, Susan Dorsey Owings.
As a young girl, Edith suffered from what would now be diagnosed a 'learning disability' with regards to reading and spelling. She did, however, show an exceptional aptitude for mathematics and card games, especially duplicate whist.
Edith and her sibling's childhoods would be one filled with tragedy. Her father died when she was only 7 years old. Her mother aslo died away five years later.
Edith and her siblings, now orphaned at the age of 12, were brought up for a time by her uncle. He served as her legal guardian for a short time before sending her to boarding school in Maryland. Once she came of age at 18, she inherited a small amount of money from her parents' estate.
Edith Clarke’s ascension: AT&T and MIT’s EE Program
She dutifully studied mathematics and astronomy at Vassar College and graduated with Phi Beta Kappa honors in 1908. Her education was funded using her inheritance.
Post graduation, Edith taught mathematics and physics at a private girls' school in San Francisco. She then moved positions to teach at Marshall College in Huntington, West Virginia.
In the autumn of 1911, Edith Clarke enrolled as a civil engineering student at the University of Wisconsin-Madison.
During the summer break after her first year, in 1912, she worked as a "Computer Assistant" to AT & T research engineer Dr. George Campbell. Edith would be so gripped by the work that she decided to stay on at AT & T to train and manage a group of human "computers" -- mathematicians (most commonly women) who quickly calculated figures as part of larger computing systems.
Campbell, at that time, was applying mathematical methods to solve problems associated with the long-distance transmission of electricity. Clarke became enthralled with the work and attended night school, studying electrical engineering at Columbia University.
While working for GE, Clark became part of the company's effort to build the first transcontinental telephone line. This line was to run from between New York and California. Despite the challenge of the project she was still drawn to engineering. Her ambition would see her return to full-time education.
Edith Clarke stayed with AT & T until 1918 when she left to enroll in the electrical engineering program at MIT. Here she earned her MSc. Degree in 1919, making her the first female to ever earn one at the department.
Part of her masters was the production of her thesis supervised by A. E. Kennelly entitled "Behavior of a lumpy artificial transmission line as the frequency is indefinitely increased."
Edith Clarke joins General Electric
Despite her successes time at MIT, Clarke couldn't find work as an engineer. But she did find work elsewhere.
At this time America was rapidly electrifying. Her experience to date eventually led to one her career highlights, her first invention the Clarke Calculator.
In 1921, with her calculator complete, she filed for a patent and was granted one in 1925.
It was to be employed in solving electric power transmission line problems, especially distances as long as 250 miles (402 km).
"She was one of the engineers who really understood and expanded Charles Steinmetz’s equations of alternating current theory,” says GE historian Chris Hunter. Chris is also the curator at the Schenectady Museum of Innovation and Science.
Clarke's Graphical Calculator, a Great Tool for Engineers
According to Clarke herself “if accuracy is desired in calculations for long [transmission] lines, it is absolutely necessary to take into consideration the uniformly distributed inductance and capacity in the line.”
So she devised the Clarke Calculator, which was a simple graph-based calculator for solving line equations involving hyperbolic functions. Edith's creation would allow electrical engineers to greatly simplify calculations for inductance and capacitance in power transmission lines.
The tool also supported Clarke’s work to gather data about the power grid and "can be seen as the first step toward “smart grid” technology according to the U.S. Department of Energy.
Edith Becomes a Professor of Physics
The same year as she filed her patent -- still unable to find work as an engineer -- Edith took leave from GE to work in Turkey. At this time Turkey was in the throes of shedding Ottoman Rule.
She took on a position as a Professor of Physics at the Constantinople Women's College. Her ambition was to teach the rudiments of physics to lead members of Armenian, Turkish, Arabian, Greek and Russian students at the college.
Constantinople (now Istanbul) was occupied by British, French and Italian Forces after the conclusion of the WW1 during Clarke's stay there.
Clarke stayed in Turkey for roughly a year and then return to GE as a salaried electrical engineer in 1923. Her lifetime ambition had finally been realized.
This very act would, once again, make Edith Clarke a first - the first woman professionally employed as an electrical engineer in the United States.
Later in 1926, Edith Clarke became the first woman to present a paper to the American Institute of Electrical Engineers (AIEE). It would be of critical national importance.
The paper, called Steady-state stability in transmission systems-calculation by means of equivalent circuits or circle diagrams, apparently gripped the AIEE audience.
During the 1920's transmission lines were getting longer and longer. Longer lines came with associated greater loads and more chances of system instability.
Mathematical models at the time were wholly inadequate when applied to anything other than small systems. Edith realized this and would apply a mathematical technique called the method of symmetrical components to provide a means of modeling a power system and its behavior.
With this technique, electrical engineers were suddenly able to determine the characteristics essential to analyzing large systems.
Edith Pioneered Data Analysis
Clarke would leave GE in 1945 after 25 years with the company. Throughout her time with GE, Edith wrote and published papers dealing with power and transmission that remain some of the industry's biggest insights.
Edith also figured out how to use an analyzer to obtain data about power networks, arguably the first step leading to the smart grid.
“She translated what many engineers found to be esoteric mathematical methods into graphs or simpler forms during a time when power systems were becoming more complex and when the initial efforts were being made to develop electromechanical aids [like computers] to [help with] problem solving,” Brittain writes.
In retirement, she returned to teaching and found a positiona at the University of Texas at Austin.
Here she continued breaking records and became the first-ever female EE professor in the United States. She remained with the university until she retired in 1956.
In an interview with the Daily Texan in 1948, Clarke observed: "There is no demand for women engineers, as such, as there are for women doctors; but there's always a demand for anyone who can do a good piece of work."
Edith would become the first woman to be elected as a fellow of the American Institute of Electrical Engineers. This would eventually become the Institute of Electrical and Electronics Engineers, IEEE.
Edith Clarke was awarded a lifetime achievement award from the Society of Women Engineers. This award cited her contributions to "the field in the form of her simplifying charts and her work in system instability."
Edith died October the 29th, 1959 in Olney, Maryland. Her career and achievements would be held in high esteem by fellow engineers for many years.
Edith Clarke, a renowned writer: textbooks and papers still influential today
"Prolific writer" seems like an understatement in describing Edith Clarke's writing and publishing habits. Much of her work involved producing useful papers on power distribution and synchronous machines.
She also wrote comprehensive Electrical Engineering textbooks that were often used in engineering schools and colleges. She would also receive two patents relating to electrical power distribution.
Two of her later papers won awards from the AIEE: the Best Regional Paper Prize in 1932 and the Best National Paper Prize in 1941.
Edith Clarke would write her highly influential book, Circuit Analysis of A-C Power Systems. The book was a compilation of notes and lectures she gave over a period years at Central Station Engineering Department of the General Electric Company in Schenectady, New York.
Starting in 1928 the notes were extended and revised for new groups of men entering the department. Practical problems in power system performance with numerical solutions were added from time to time and they were presented by operating engineers.
As the notes were helpful to members of the department and others receiving the, it was suggested that they are put in book form. This she did and Volume 1 was published in 1941 with a second in 1950.
Edith Clarke's legacy
Dr. James E. Brittain's paper, From Computer to Electrical Engineer - the Remarkable Career of Edith Clarke explained just how important Edith was for both engineering and computing:
"Edith Clarke's engineering career had as its central theme the development and dissemination of mathematical methods that tended to simplify and reduce the time spent in laborious calculations in solving problems in the design and operation of electrical power systems."
James continues "She translated what many engineers found to be esoteric mathematical methods into graphs or simpler forms during a time when power systems were becoming more complex and when the initial efforts were being made to develop electromechanical aids to problem-solving."
"As a woman who worked in an environment traditionally dominated by men, she demonstrated effectively that women could perform at least as well as men if given the opportunity. Her outstanding achievements provided an inspiring example for the next generation of women with aspirations to become career engineers."
Edith would also become the first female engineer to achieve professional standing with the Engineering Honor Society, Tau Beta Pi.
In 2015 she was posthumously honored by being inducted into the National Inventors Hall of Fame (NIHF).
Edith was one of 22 engineers and scientists inducted in the NIHF who were, at some point, employed by GE. All of these are men except Ms. Clarke and physicist Katherine Blodgett.
This act let Edith Clarke join the ranks of Nicola Tesla; Nobel Prize winner Irving Langmuir; Charles Brush, who built the first wind turbine; William Coolidge, who revolutionized the X-ray machine; and Robert Hall and Nick Holonyak, who pioneered LED technology and came close to a Nobel a few years ago.