Whenever someone thinks about silent cinema the image of the laughing villain, twirling his mustache, and tying the hapless blonde beauty to the railroad, pops up in our collective memory. But in which movie (or movies) did that particular image first appear?
The link in Neil Baker's comment to Luke McKernan's "Tied to the tracks" article also gives a very detailed history of a woman being tied to the tracks, occasionally by the evil villain twirling his moustache.
And all those who do know silent films know that such scenes were hackneyed even before films were invented, and the few films that did show them did so as parody.
Luke traces it back to an 1867 staged melodrama by Augustin Daly called Under the Gaslight, where a woman saves a man from the tracks in the nick of time. Later plays copied this, and at some point it switched to a man saving a woman.
In early film, such stage melodrama was out-of-date -- "so no more twirling of moustaches if you wanted your villain to be taken seriously" -- and instead film capitalised on recreating realism.
However films such as 1905's The Train Wreckers and 1911's The Attempt on the Special played it straight, where an unconscious woman is left on the tracks. But she was left there by a gang rather than the moustachioed villain.
The film that established the parodic idea, and which is often used to illustrate it, is Keystone’s Barney Oldfield’s Race for a Life (1913), featuring real-life motor racer Barney Oldfield, Ford Sterling as the moustachioed villain and Mabel Normand as the victim.
The black moustache-twirling villain, often enshrouded in black and with a top hat, and the heroine in distress are two of the six stock characters of Victorian stage melodrama:
The Victorian stage melodrama featured, six stock characters: the hero, the villain, the heroine, an aged parent, a sidekick and a servant of the aged parent engaged in a sensational plot featuring themes of love and murder. Often the good but not very clever hero is duped by a scheming villain, who has eyes on the damsel in distress until fate intervenes at the end to ensure the triumph of good over evil.
This made me think of an 1913 movie that Mack Sennett made called Barney Oldfield's Race for a Life. If I recall correctly, this film featured not only a mustachioed villain, but a woman tied to the train tracks!
Possibly the earliest version.