AS YOU read this, the United States Patent Office has issued patents for over 4 million inventions. That figure is an astonishing testimony to American ingenuity, yet in all likelihood, very few of those patented inventions will make a major impact on our day-to-day life in the way that the electric light bulb, the telephone, the automobile, and the Internet have done. And few if any of the inventors will achieve the fame of a Thomas Edison or a Henry Ford. That’s a shame, because over the years inventors have come up with products that make our lives easier, more convenient, even safer. And the inventors I have in mind are all American women.
You’ve probably never heard of any the women inventors included here—except, perhaps, Stephanie Kwolek, the inventor of Kevlar. Why they’ve been ignored by history is anybody’s guess, particularly when you consider that they dreamed up innovations that many Americans use everyday—windshield wipers, brake lights, dishwashers, disposable diapers. Like their much more famous male colleagues—Edison and Ford mentioned above, Benjamin Franklin, Eli Whitney, Samuel Morse—these women saw a problem and decided to fix it. And fix it they did.
The Square-bottom Paper Bag
NO ONE KNOWS who the first shopkeeper was, but he probably hadn’t been in business long before he realized that shoppers would buy more stuff if they had a simple, sturdy receptacle in which to pack up their purchases and carry them home. Francis Wolle (1817-1893), a Moravian schoolteacher from Bethlehem, Pennsylvania, came up with a solution in 1852, when he patented the first paper bag. But actually, it was more of a large envelope than a bag, and the narrow bottom failed to achieve what shopkeepers had hoped.
The true square-bottom paper bag was invented by Margaret Knight (1839-1914) in 1868. Originally from York, Maine, she had worked in textile mills from the time she was nine years old. Around the year 1867 she took a job at the Columbia Paper Bag Company in Springfield, Massachusetts, where, of course, the envelope-style bags were made. Knight had a flare for mechanics, and began designing a machine that would cut the paper, fold it into a square shape, and glue the bottom. She had constructed her prototype in wood, but to file for a patent she had to have one made of iron. Knight was working on the metal version when the factory received a visitor, a man named Charles Annan, who showed tremendous interest in her machine. He studied it so closely that when he left the factory, he was able to make a copy and apply for a patent ahead of Knight.
Margaret Knight was not about to let her idea be stolen. She filed suit against Annan charging him with patent interference. During the trial Annan told that court that it was absurd to believe a woman could comprehend the complexities of a paper bag-making machine. When Knight produced a small mountain of notes, designs, and diary entries describing her work, it became clear to the court that she most certainly did understand the complexities of the machine—and that she had invented it. The judge ruled in Knight’s favor.
JOSEPHINE COCHRANE (1839-1913) was well-to-do; she had a kitchen full of servants to wash her dishes. But the servants were often careless and Cochrane was tired of seeing her fine china nicked and chipped. To ensure that her dinnerware was treated with the proper degree of care, she started washing the dishes herself—and discovered quickly how tedious that job was. There had to be a better way,
In a shed behind her house Cochrane built a rack that held dishes, cups, and bowls in place. The rack lay flat inside a copper boiler. A motor turned the rack and soapy water squirted up, washing the dirty dishes. Cochrane used her prototype in her own kitchen, and made copies for her friends. In 1886 she patented her invention. Restaurant and hotel owners were the first to recognize the time-saving (and china-saving) possibilities of the dishwasher; to meet this new demand Cochrane founded the Cochrane Crescent Washing Machine Company. At the World’s Fair in Chicago in 1893 she demonstrated her machine to the public, and won awards for mechanical design and durability.
Businesses remained the primary market for Cochrane’s invention. In the late 1890s and early 1900s, most American homes did not have large hot water heaters—and for one load of dishes, Cochrane’s dishwasher went through a lot of hot water. It was not until the 1950s, about 40 years after Cochrane’s death, that the dishwasher finally began to appear in American kitchens. Home water heaters were now much larger, and housewives were eager to own the latest labor-saving appliance. Cochrane’s company, by the way, was acquired by KitchenAid, a member of the Whirlpool Corporation.
The Windshield Wiper
THE FIRST AUTOMOBILES did not come equipped with anything to keep the windshield clear of snow, rain, or condensation. If it became too hard to see, the driver pulled over to the side of the road and wiped off the windshield with a rag. In a heavy rain or snow storm, drivers had no other option than to wait it out.
In 1903 Mary Anderson (1866-1953) traveled with friends from her home in Alabama to New York City. They arrived just as a blizzard hit. While sitting in a trolley car, Anderson watched as the trolley’s driver tried—unsuccessfully—to keep his windshield clear of snow and sleet by making repeated stops to wipe the glass. When she returned to her home in Birmingham, she sketched a simple arm on which was mounted a rubber blade. The arm would be attached to the top of the frame of the windshield, and connected to a lever inside the car. The driver operated the wiper manually, turning the lever back and forth to clear the glass of precipitation.
Anderson patented her windshield wiper in 1905, and tried to sell the rights to a Canadian automobile manufacturer. The car company turned her down, writing, “We do not consider it to be of such commercial value as would warrant our undertaking its sale.” Other manufacturers rejected her invention because they believed the movement of the wiper would distract drivers and cause car crashes.
After 17 years Anderson’s patent expired and she did not renew it. This was a major mistake, as the automobile industry was on the verge of a boom. As new models were introduced, the windshield wiper became standard equipment. If Mary Anderson had held on to her patent, she would have become a millionaire. Instead, she spent the rest of her life as the owner and manager of the Fairmont Apartments on 21st Street South in Birmingham, Alabama.
Turn and Brake Signals
DURING THE SILENT movie era Florence Lawrence (1886-1938), originally from Canada, was a star—but hardly a soul knew her name. On-screen credits were rare in the early part of the 20th century, but Lawrence had such a lovely, memorable face that she was known to audiences as “The Biograph Girl” (early in her career, she worked exclusively with Thomas Edison’s Biograph Studios).
In 1910, Carl Laemmle (the future founder of Universal Pictures) started the Independent Motion Picture Company to make movies, and convinced Lawrence to sign with him. He paid her lavishly and instigated a series of publicity stunts to keep her in the public eye. The movie-going public was dazzled by Lawrence’s glamour, and she became Hollywood’s first movie star.
Lawrence was also one of the first women in Hollywood to have her own car. She bought her first before 1913, and became an ardent cheerleader for the automobile. She was also an inveterate tinkerer, and was soon designing instruments that would improve it. Her initial idea was a signal that would indicate to other drivers when a car was about to turn right or left. Lawrence’s turn signals were little wooden arms attached to the rear of the car that the driver operated by pushing buttons on the dashboard. The stop signal, also a wooden arm, was activated when the driver stepped on the brake pedal. These ingenious inventions made operating a car much safer, yet Lawrence never patented them. Consequently when automakers began incorporating turn and brake indicators into the design of their cars, she received no royalties.
Lawrence’s movie career did not fare well either. She was replaced at IMP by Mary Pickford, known as “America’s Sweetheart.” By 1920 fewer studios were asking her to appear in their movies. In 1938, after suffering burns in a fire, being widowed twice and divorced once, Florence Lawrence committed suicide.
KATHERINE BLODGETT'S (1898-1979) aptitude in science won her a scholarship to Bryn Mawr College, where she studied mathematics and physics. After graduating from Bryn Mawr she went on to the University of Chicago for a master’s degree in physics, which she completed in only one year. She was only 20 years old when she was hired by General Electric—the first woman research scientist to work in the company’s laboratory in Schenectady, New York.
At the GE lab Blodgett worked with Irving Langmuir, a future Nobel Prize winner. Together they generated a flurry of patents for improvements to everything from vacuum pumps to light bulbs. At one point Langmuir was fiddling around with some oily substances and found that the oils left a film one-molecule-thick on the surface of water. He called these oil slicks monomolecular coatings, wondered if they had a practical application, and asked Blodgett to see what she could make of it. Blodgett observed that the oily film reduced glare on the surface of water, and from that observation she deduced that the film would reduce glare on glass.
Through trial and error, Blodgett found that it took 44 coats, each one molecule thick, of barium stearate film to block glare. Interestingly, although the treatment eliminated glare completely, 99 percent of light still passed through the glass. Blodgett had invented nonreflecting glass. It would be used for eyeglasses, telescopes, microscopes, camera lenses, even submarine periscopes. The problem with Blodgett’s invention, however, was that the coating was easy to rub off. It would be other researchers who, working with Blodgett’s initial results, found a way to apply a more durable coating to glass.
And Blodgett’s film had other applications. During World War II the film was applied to the wings of fighter planes to make them ice-resistant.
Blodgett spent almost all of her life in Schenectady, New York, the place where she had been born. Before her death at age 81, her hometown celebrated their most famous citizen with “Katherine Blodgett Day.”
MARION O’BRIEN DONOVAN (1917-1998) grew up in a family of inventors—her father and her uncle had invented a lathe to grind gears for automobiles. As a little girl, she spent much of her time in her family’s machine shop where she learned that often there were innovative solutions to everyday problems.
At Rosemont College outside Philadelphia, O’Brien studied English literature rather than engineering, and after graduation she moved to New York City where she took a job as assistant beauty editor at Vogue magazine. After her marriage to James Donovan, she quit her job to start a family in Westport, Connecticut.
In the 1940s, as a wife and mother of small children, she turned her ingenuity to building a better diaper. At the time diapers were cloth and fastened with pins. Every soiled diaper had to be washed, along with the sheet the baby had been laying on. Donovan’s first invention was a leakproof, waterproof diaper cover. She started out cutting up plastic shower curtains for her prototype, and later found that nylon not only worked better, but—unlike the plastic—it did not give the baby diaper rash. And instead of pins, Donovan’s diaper cover was fastened with snaps. Her invention debuted at Saks Fifth Avenue in New York in 1949 and was (no surprise) an instant hit with harried moms. Donovan received a patent for her diaper cover in 1951.
The diapers were now waterproof, but the chore of washing load after load every day still remained. In 1950 she developed a disposable paper diaper that drew moisture away from the baby’s bottom, once again in the interests of avoiding diaper rash. Incredibly, the idea did not catch on. Ten years would pass before a major U.S. manufacturer, Victor Mills, saw the genius of Donovan’s idea and introduced the world to Pampers.
Once her own children had grown up, Donovan returned to college, took a degree in architecture from Yale, and designed and built a new house for her family in Greenwich, Connecticut. By the time of her death she had been awarded a dozen patents.
IN 1946, 23-year-old Stephanie Kwolek (1923-i) graduated with a degree in chemistry from Margaret Morrison Carnegie College (the women’s division of Carnegie Mellon University). She wanted to go to medical school but didn’t have the money, so she took a job in the synthetic fibers division of Du Pont. The company was the leader in creating synthetic fibers, having already brought nylon, Dacron polyester, and Lycra to the market. Kwolek worked with aromatic polyamides, known as aramids for short. Aramids are characterized by their tight, rodlike molecules—in stark contrast to the flexible chains of molecules that Du Pont had been able to make into nylon.
Kwolek experimented with various solvents to find one that would blend with the aramid molecules to form a polymer. When she finally got the polymer, it was cloudy and watery, not clear and thick like the ones that had produced Du Pont’s most successful synthetic fabrics. The next step would be running her polymer through the “spinner” to see if it could be spun into synthetic thread. The chemist who ran the machine looked at Kwolek’s goop and refused to test it, but Kwolek persisted, and eventually persuaded him to give it a trial run. To their mutual surprise, Kwolek’s polymer was easy to spin into thread, and the thread it produced was light but extremely strong.
As she studied her new fiber, she learned that it was five times stronger than steel of the same weight. Kwolek’s discovery went on the market in 1971 under the name of Kevlar®. Today Kevlar® is used in everything from bridge cables to fishing line to radial tires to fiberoptic cable. But it is best known as a component of lightweight body armor.
Margaret knight, Josephine Cochrane, Mary Anderson, Florence Lawrence, Katherine Blodgett, Marion O’Brien Donovan, and Stephanie Kwolek all belong to that great fraternity—make that sorority—of American tinkerers. It seems to be hardwired into our national character to see a frustrating problem and respond by spending hours in the garage or the workshop to find a practical solution. That’s how we got the Wright brothers’ airplane, Steve Jobs and Steve Wozniak’s Apple computer, and Josephine Cochrane’s dishwasher.