El Dorado Jones

Eldorado Jones (1860–1932) was an American inventor nicknamed the "Iron Woman". Her factory in Moline, Illinois, mainly employed women over the age of 40. She is best known for inventing an airplane muffler, but also developed a lightweight electric iron, a travel-size ironing board, a collapsible hat-rack, and an "anti-damp salt shaker".

Jones was born in 1860 in Palmyra, Missouri. Her family moved to St. Louis, and her father, Alonzo Jones, deserted them. Eldorado first took work as a teacher in Lafayette, Indiana; detesting this job, she became a stenographer at an insurance company in Chicago.

By 1913, however, she had become an inventor, and opened an all-women factory in Moline, Illinois, dedicated to manufacturing her creations. She devised an airplane muffler in 1919. Following tests at Roosevelt Field, she patented the invention in 1923. Time magazine described the muffler in action:

Puffing upon one cigaret after another, Miss Jones directed mechanics in attaching to the Cirrus engine of a Moth biplane a muffler of her own invention. As the plane sped along the runway and over the hangars there were noises—of thrumming propeller, snapping pistons, vibrating metal—but there was no bark of exhaust.

As Popular Science reported in 1931, the muffler reduced noise without reducing power. That same year, Modern Mechanics and Inventions described it as "the first successful exhaust muffler for airplane engines." The muffler used "a series of small pinwheels which 'chew up' the sound waves and retard the passage of exhaust gases without creating undue back pressure upon the engine."

The New York Times noted Jones's "energy, her self-reliance, and her general distrust of men." According to the historian Anne MacDonald, Jones's dim view of the opposite gender made it harder for her to capitalize on the muffler.

She did not meet with the success she sought, and her death in 1932 was observed in the New York Times with the headline, Woman Inventor Dies in Poverty. The obituary closed with a quotation from Jones: "Do not forget to exploit men all you can. Because if you don't, they will exploit you."