My Margery Ferguson married Thomas Davey. They lived in New York State. In trying to find their ancestry, I did quite a bit of research on the families. I've posted my direct Davey/Davy information at my website, www.nancylanni.com
and that might help solve Elizabeth's ancestry, though I didn't find their marriage in my database. I haven't made the Ferguson connection as yet. I have 2 James Daveys in my database, one born in 1800, one born in 1848.
I'd very much like to have copies of your photos, and would be pleased to purchase the other Davey/Ferguson photos from the antique store.
You may contact me at firstname.lastname@example.org
Thanks for posting. It will be interesting following this couple out West.