Hi Cats, what a fabulous photo, I'm so envious! Likely taken between 1855 and 1865, when glass or Ambrotype photos were being produced.
How about making a higher-resolution scan, say 300-600 dpi, and posting it on the Photo Restoration board for a little tidy? There's an area lower left that could be cleaned up a bit...and you might find out some more things about the picture!
You will need to change the file name slightly, just adding a letter or number will do.
Cheers,
China