Antique Desk Late 1800s early 1900s

This desk was my great grandfathers. My grandmother estimated that it was made in 1890-1910. They lived in Deposit, NY (near Binghamton). Unfortunately, my father refinished the desk thirty years ago and added the hideous green felt to the top. I'm not sure if the nails and screws are all original. The wood certainly is. On the bottom of the desk are the initials "HJG". The "G" is centered and much larger than the "HJ." It appears to be written in pencil, but it may be coal. My father did NOT refinish the bottom of the desk, so it's possible the initials are by the maker. I found a furniture company called HJ Gelzer & Son in Michigan that began making furniture in 1913, so that may be a lead.

Any help in tracking the orgins and value of this desk would be greatly appreciated.

Thanks,

Marc