The first film adaptation of Mary Shelley's Frankenstein is a black-and-white (and color-tinted and color-toned black-and-white) one-reeler made in 1910 by Edison Studios. This silent movie is only about 15 minutes long (give or take a couple minutes), so it's not surprising that it isn't completely faithful to the novel. It disregards the book's epistolary form, ignores most of the philosophical issues raised by Shelley, avoids some of the more violent and macabre elements of the story, and both condenses and changes the plot.
While the film seems stagy compared to some other silents of the time period, I have to give it credit for at least one thing: the monster has long hair, as he did in the novel. Compare the following illustration from the 1831 edition of Frankenstein...
to Boris Karloff's famous portrayal of the monster in the 1931 film version.
One of the advantages of the film adaptations is that we get to see the creation of the monster. In the 1910 film, the monster isn't created by assembling body parts from corpses and animating them with electricity, as his creation is portrayed in the 1931 movie. Instead, the monster is created by a form of alchemy.
Despite its flaws, I think the 1910 film is kinda interesting. It is in the public domain and is available for viewing at the Internet Archive.
By the way, this wasn't the only silent version of Frankenstein.
There was a feature-length (5-reel) version released in 1915 (and re-released with additional footage in 1916) called Life Without a Soul. Unfortunately, the film is presumed lost, although at least one person has claimed to have seen a print.