I scanned this cropped image from a historical series of about three dozen postcards of the Mountain View and Indian Lake, NY, area, from antique glass plates, which were in their original sleeves. Most had the numbers from past reorders for printing jobs that were done long ago, although many had no sleeves at all, and had been stored loose in the box. Since this series of postcards utilized a numerical system, it was easy to determine that this large collection is incomplete, as I later encountered slides taken of several other postcards from another source, obviously part of this series, but now missing. I'm unsure if the slides were created from these original plates, or whether they were created from prints. The photographer is unknown, as is the original publisher, or even the original owner of the negatives.