Tinkle your bells and fasten your helmet — it's National Bike Month, which means it's time to delve into the history of this most feminist of machines. Yes, you read that correctly. In ways both explicit and subtle, the invention and popularization of the humble two-wheeled bicycle in the 19th century helped move the cause of female equality and freedom forward in the modern world; even today, there is no more feminist way to get around.

Before the bicycle came along, women were expected to progress on foot, in carriages, or on horseback, always while supervised and preferably with the utmost slowness and delicacy. How you traveled denoted your class; to be walking the streets was seen as a highly suspect activity, and was tightly moderated among 19th century women of the upper classes, who were meant to stay largely indoors or to venture outside only with chaperones and in acceptable public spaces.

Various inventions changed that, from the department store to the car — but the bicycle was likely the most crucial of them all. Inexpensive, easy to use and capable of high speeds, the velocipede, as it was then known (the women who rode them were known as "velocipedestriennes" at the time), would remake the world for women in the 19th century, and has done so ever since. Get on your bikes and let's have some fun.

The First Bicycles Were For Men Only — But That Didn't Stop Female Bike Pioneers Alexander Turnbull Library The first bicycles, developed in the early 19th century, were almost exclusively for men; the earliest was known as the "bone-shaker," and appears to have been marketed as a macho accessory, though one historian records adventurous Parisian women riding it around the Bois de Bologne. Bicycles were, up until 1890s, considered masculine accessories, for multiple reasons — one of which was the fact that they couldn't be ridden sidesaddle, which was considered the only delicate way for a woman to ride anything. (Women of the era who rode astride horses rather than side-on were widely mocked as odd and unfeminine.) Then came the invention of the "safety bicycle," which changed everything. Its wheels were the same size and its tires were inflated, and it was deemed appropriate for children — and, some women decided, for them as well. This was a radical decision for a lot of reasons: Bicycles were meant to be used by male riders only; you could ride them rapidly and without a chaperone; and you could use them to exercise freely in public. "To men," an editorial from 1896, quoted in the excellent cycling book Wheels Of Change, noted, "the bicycle in the beginning was merely a new toy, another machine added to the long list of devices they knew in their work and play. To women, it was a steed on which they rode into a new world."

People Saw The Bicycle As A Sexual Threat Cycle Confident on Twitter Bicycling didn't just give women a way to get around freely; it also, surprisingly, played a role in women's sexual liberation — purely because some people believed that if women went around straddling something, they would start having orgasms all over the place (which, needless to say, these people thought was a bad thing). "Traditionalists," Andrew Denning explains in The Fin-De-Siecle World, "fulminated against the idea of the bicycle as an instrument that would instigate a sexual awakening, whether personal, as many people expressed trepidation about a woman straddling a bicycle seat and experiencing the shocks and vibrations of the road, or socially, as bicycles gave women the freedom to escape the watchful eyes of parents and chaperones." Bicycles: The 19th century's shocking vibrator-slash-Uber alternative. No wonder feminists loved them. However, not every 19th century sexist was entirely upset by the idea of women going out and getting exercise. It's noted in City Cycling that some thinkers, hilariously enough, recommended the idea because the strength of cycling would make them "more fit for motherhood." Women who wanted approval from their doctors for their cycling habit, though, also ran the risk that they'd be informed that the bicycle would rattle their innards and leave them vulnerable to everything from tuberculosis to gout. They were also informed that "bicycle face," the tense expression of concentration required for dodging traffic, would ruin their beauty, and that the whole practice would make them bowlegged from too much pedaling. Women kept pedaling regardless.

Bicycles Helped Women Shed Restrictive Clothing Brown University Library The phenomenon of the bicycle also helped women get out of long, restrictive skirts — because while many of them were perfectly happy cycling decorously in ankle-skimmers, some found the practicalities rather unbearable. The beginning of the end for the restrictive skirt was obvious even in 1868, in the earliest women's bicycling race in history, which took place in France; it's recorded that many of the women wore scandalously short skirts to help them to pedal more effectively and avoid accidents. The accident issue was a real one. By the 1890s, one woman, the English rider Helena Swanwick, point-blank refused to wear a skirt again after a ride of which she declared, "It is an unpleasant experience to be hurled onto [the ground] and find that one's skirt has been so tightly wound around the pedal that one cannot even get up to unwind it." The solution? Bicycling bloomers, or a "bicycling costume," as it was known at the time. They still went to the ankles, and were quite voluminous, but they allowed more movement and were far safer. However, the trend for bicycling outfits met with approbation from many parts of society. The New York Times reported in the 1890s that, while Parisian women were fast getting into the bicycling costumes, only one woman had dared to wear bloomers while riding her bicycle in Newport, and she only did it at night. Male approval for the bicycling costume wasn't strong; in New York in 1895, a society formed of men who pledged never to talk to bloomer-wearing women and to attempt to "render such costumes unpopular." Still, several men appeared in favor of the new innovation — though perhaps not in the feminist ally way we'd hope. The Atlantic reports on a remarkable document from 1897 in which the gentleman W.J. Lambton gives his opinion on various U.S. cities — based solely on the shapeliness of the legs and ankles of their lady cyclists, complete with illustrations.