I have some correspondence, her home address, a photo of her as Bert Blair, America’s Famous Motor Girl, IIRC, and a few other factual tidbits that may help. I’ll dig it out and post what I have in the next few days. I didn't find her by name, Bert Blair, or the original movie, Sign of the Zodiac, in the IMDB or on Google. Thank you!
Her screen name was Bert Blair, and the movie she mentions is the original “Sign of the Zodiac.” She worked for the Minerva Film Company which suffered a major fire and disappeared in 1929, as far as I know. She also billed herself as Bert Blair, America’s Famous Motor Girl, IIRC. She planned an Around the World tour by automobile in 1925. Whether or not she completed that trip is unknown. She received a .38 Military and Police pistol from Smith & Wesson for protection (and promotion of Smith & Wesson) on her trip. She is not currently listed in the IMDB or found with online searches. Does anyone recall Bert Blair from the 1920s? Thank you!
You might want to try asking on the Silent Film board of IMDb at http://www.imdb.com/board/bd0000073/threads/. I don't know if you will get a response there, but there seems to be an intelligent level of discussion on that board so at least it seems worth asking there.