yeah, it is wrong that so many silent films got lost because of volatile technologies and piss poor preservation efforts. Not having a chance to see Theda Bara in all her glory is unfair.

There is a book about London After Midnight and it reconstructs the movie out of available scripts, production notes and stills. So it is not completely gone. And there's remake called Mark of the Vampire featuring very prime very tongue-in-cheek Bela Lugosi channeling his inner Valentino and also Lionel Barrymore chewing the fuck out of the script like its Jaws.