This Women's History Month we, at the Business & IP Centre, are shining the light on female inventors. Let's hear more from the curator from our historical patent collection, Steven Campion, on just some of his favourite inventions patented by women. 

'Although women have always found solutions to the problems around them, social and historical factors mean little of this was recorded. Women inventors would have had fewer resources and faced discriminatory barriers at every step of their journey – often having their contributions downplayed or overlooked entirely.

Therefore just 62 out of the 14,359 patents granted in England between 1617 and 1852 were awarded to women. In fact before 1965, the proportion of women in the UK patent system was generally between 2% and 3%. The proportion has since risen at an accelerating pace, having reached 6.8% in 1998, and then almost doubling to reach 12.7% in 2017. As the number of women working within the STEM sector increases, we can hopefully look forward to this number rising further.

But as for those patents that have already been filed, I have collated some of the most notable and fascinating examples of problem-solving women who were at the forefront of innovation.

Before we begin, a quick caveat. Earlier patents may exist for some of the inventions given in this list but the following women are widely considered the inventor of their ‘thing’ because it worked (earlier versions didn't in some cases), or it was popular, or it is recognisable to the form as it exists today, and so on. It is also worth saying that there are many other female innovators and inventors we could have mentioned. Not all acquired patents, some weren’t given credit, many were trapped by the conditions of their time. However this is a selection of some notable examples

Mary Anderson – windscreen wiper

A copy of the U.S. patent can be seen here.

Mary Anderson visited New York City in the winter of 1903. This was the year before the subway opened and the streetcar was a popular way to get around town. During her trip it snowed heavily, forcing the streetcar drivers to frequently stop to clear the snow and ice from their windscreens. When this became unmanageable, they would instead drive with their head sticking out of an open window.

Delays and open windows of course meant discomfort for the passengers, especially someone like Anderson who was not used to the chill of a New York winter.

Knowing there had to be a solution, Anderson began work as soon as she returned to Alabama. Her finished prototype was a radially swinging rubber blade which would wipe the windscreen clear of obstruction. Fairly similar to the modern-day windscreen wiper, except Anderson’s invention was manually operated by a handle inside by the driver (in 1917 another female inventor, Charlotte Bridgwood, was granted a patent for the first electrically powered windscreen wiper).

On the 10^th November 1903, U.S. patent no. 743,801 was granted to Anderson for her ‘window-cleaning device’. Unfortunately not many people saw the worth in her invention, saying it would be a dangerous distraction to the driver. Cars were also not particularly common and Ford’s Model T was still 5 years away. Anderson therefore made no money from her patent and it eventually lapsed.

As driving became more commonplace, the windscreen wiper was eventually adapted for automotive use, today being an important safety device that is a legal requirement in most countries.

Mary Walton – pollution reducing devices

A copy of U.S. patent no. 221,880 can be seen here; the historic IP collection at the library contains a paper copy of the GB version of the patent (GB 3,512 of 1879).

A copy of U.S. patent no. 237,422 can be seen here.

Elevated trains were installed throughout the larger U.S. cities in the second half of the 19^th century, unfortunately bringing a large amount of air and noise pollution for those living nearby. Mary Walton, who lived beside the tracks in Brooklyn, worked to solve both problems, earning herself a place in history as a STEM female pioneer.

In 1879 she was granted U.S. patent no. 221,880 for ‘Improvement in locomotive and other chimneys’. Her invention reduced air pollution by diverting chimney smoke through water tanks. This process dissolved and trapped the pollutants in the water, which would later be flushed into the sewer system.

Next, she realised that wooden elements of the track were amplifying the noise of the trains. Using a model railway she built in her basement, she came up with a working solution – encasing specific sections of the track in weatherproof wooden boxes filled with sand. This successfully absorbed the majority of the vibrations; greatly reducing the noise levels. Before Anderson, many noted engineers and inventors tried and failed to find a solution, including Thomas Edison.

After successful trials, Walton was granted U.S. patent no. 237,422 in 1881. She sold the patent rights to New York City’s Metropolitan Railroad, and before long the system was in place throughout America.

Josephine Cochrane - first commercially successful dishwashing machine

A copy of the U.S. patent can be seen here; the historic IP collection at the library contains a paper copy of the GB version of the patent (GB 9,895 of 1887).

Josephine Cochrane, a 19^th century socialite, often hosted grand dinner parties at her mansion in Illinois. She was fortunate enough to have servants to wash up afterwards, but Cochrane was unhappy to discover the occasional chip in her heirloom china. She therefore decided to wash the dishes herself, though soon became bored of the task.

So bored in fact, that Cochrane designed a machine to take over. Her machine used water pressure to clean dishes held in place by wire racks – a system recognisable to anyone with a modern dishwasher.

The first few male engineers she hired predictably insisted on changing her design. They were convinced they knew better than an untrained woman, but their changes never worked. Eventually her design was built and U.S. patent no. 335,139 was granted for her ‘Dish washing machine’ in 1886.

At the time the machine was too expensive for most homeowners and required more hot water than the typical home could generate. But after winning a top prize at the 1893 World’s Fair in Chicago, orders poured in from hotels, restaurants, and hospitals.

In 1898 Cochrane started her own company which she managed until her death in 1913. In 1926 the company was acquired by Hobart, which went on to produce the first successful home dishwashers under the KitchenAid brand in the 1940s.

Today half of all UK households have a dishwasher thanks to the pioneering work of Josephine Cochrane – presumably the other half wishes they had room for one.

Margaret Knight - machine for making flat-bottomed paper bags

A copy of the U.S. patent can be seen here.

In 1867 Margaret Knight started work at a paper bag factory. At the time, mass produced paper bags had envelope style bottoms, which were both weak and narrow. Flat-bottomed bags were stronger and made packing easier, but there was no machine that could make these. Instead a production line of 30 women were employed to cut, fold, and glue these together. Flat-bottomed bags were therefore expensive and uncommon.

Knight was an inventor at heart. At the age of just 12 she had invented a loom safety device that was used extensively by the cotton industry (but unfortunately not patented). She therefore soon developed a machine that could manufacture flat-bottomed bags from start to finish – something male inventors had been trying and failing to do for years. In 1871 Knight applied for a patent, but was rejected as a similar machine was recently patented by Charles Annan.

Before her application, Knight had visited several machine shops in order to create an iron prototype. At one of these, Annan saw the plans and decided to steal the invention. Knight filed a patent interference lawsuit, with a mass of documentation and witness testimony on her side. Annan could only really state that no woman could design such a machine. Knight of course won, and U.S. patent no. 116,842 was granted for her ‘Improvement in paper-bag machines’ in 1871.

Knight would continue to innovate, being awarded many more patents over the course of her lifetime.

Melitta Bentz – the coffee filter

The industrial property right was granted with registration on page 1145 of the 8^th July 1908 edition of the patent gazette of the Imperial Patent Office in Berlin – see image.

Like many of us, Melitta Bentz enjoyed starting her morning with a cup of coffee. What she didn’t enjoy was the bitter tasting coffee grounds still left floating in her cup.

At the time, coffee was usually brewed by pouring ground coffee into hot water and then waiting for the grounds to settle to the bottom. Sieves and cloth bags would help, but they either let too many coffee grounds through, or would be so narrow that the coffee would be cold by the time it was filtered.

One day Bentz had a flash of inspiration. She drilled holes into the bottom of a brass pot, which she then sat on top of a cup. Next, she placed a piece of blotting paper from her son’s school exercise book into the bottom of the pot, adding freshly ground coffee on top. Bentz then poured hot water into the pot and watched as clean, filtered coffee dripped into the cup below – she had invented pour-over coffee and the coffee filter.

In 1908 Bentz was granted utility model 343,556 for her ‘Coffee filter with a domed underside, recessed bottom and inclined flow holes’ from the patent office in Berlin. The same year she founded the company ‘Melitta’ and began to sell her pot and filter paper. In the 1930s Melitta would go on to create the cone shaped filter and today, the still family owned business, produces over 50 million filters a day.

Despite the ease of modern coffee brewing methods, pour over coffee has remained popular amongst coffee lovers, who appreciate the high level of control it provides.

Elizabeth Magie – the landlord’s game

A copy of the U.S. patent can be seen here.

For the longest time it was an accepted fact that Monopoly was invented by Charles Darrow in 1933. It wasn’t until the 1970s that a decade long trademark infringement lawsuit revealed the actual truth – Monopoly was heavily based on another board game patented decades earlier by a progressive woman called Elizabeth Magie.

Magie was granted U.S. patent no. 748,626 in 1904 for her board game ‘The Landlord's Game’. It was designed to illustrate the anti-monopolist theories of 19^th century economist Henry George, and as such it came with two rule sets – one monopolist, the other anti-monopolist. The idea being players would see the latter was the morally correct choice.

Failing to find a publisher, Magie self-published the game in 1906. It sold poorly, but a local economics professor picked up a copy and played it with his students. At the time it was not uncommon to create handmade versions of published games, and that’s exactly what several of these students did, and it’s exactly what several friends of these students did, and so on.

As the homemade versions spread, the game would change a little here and there. New house rules would be added and the street names would be updated to reflect local towns. Ironically, people thought it was more fun to own land, charge rent, and bankrupt friends and family, and so the anti-monopolist rules were left permanently to one-side.

Fast forward to 1932, and Charles Darrow is introduced to a home-made version of the game. He immediately creates his own copy and starts to sell it under the name ‘Monopoly’. It does well and he sells the board game rights, becoming the first millionaire game designer in history. By contrast, Magie is said to have earned only $500 from her board game.

Hedy Lamarr – frequency-hopping

A copy of the U.S. patent can be seen here.

Hedy Lamarr was a Hollywood icon who was promoted as ‘the most beautiful woman in film’. She was so startlingly beautiful in fact, that her brilliant mind was largely overlooked her entire life. It wasn’t until her later years, and sadly really only after her death that the world would learn of her part in the development of the wireless technologies we take for granted today.

It was World War Two, and Lamarr had heard that German U-boats were easily jamming the signals that guided the radio-controlled Allied torpedoes. She hit on a brilliant solution – if the signal hopped from frequency to frequency rapidly, then it would be near impossible to detect and jam.

She asked a composer called George Antheil to help realise her invention, and together they created a system that used paper piano rolls, perforated with a complex and random pattern, to make a signal hop rapidly between 88 frequencies – the same number of keys on a piano.

U.S. patent no. 2,292,387 was granted for their ‘Secret communication system’ in 1942, however the Navy declined taking their idea forward. It is thought the invention was not taken seriously as it was created by an actor who was world famous for her beauty.

However during the Cuban Missile Crisis in 1962, about three years after the patent had expired, the technology was adapted and in use. Fast forward many more years and frequency-hopping would be foundational to modern wireless technologies, such as GPS, Bluetooth, and secure Wi-Fi.'

For more on intellectual property and female founders, you can visit at the Business & IP Centre resources at bl.uk/bipc.