Sarah Bush Johnston photograph

[Steve]

Without a provenance and with the inscription being useless as evidence for the new photo's authenticity the only option for verifying it as Sarah would be a forensic visual comparison of the newly found photo with the authenticated photo.

Just by looking at the photos, it seems like Sarah might have a slightly rounder head shape than the woman in the new photo but I suppose that could be an illusion caused by Sarah's bonnet. You also have to take into account the photo of Sarah is a copy from the original with some features slightly "retouched". I don't think the online images of the photos have a high enough resolution to really compare the womens' features myself, so I'll just put myself down as neutral/inconclusive on that question for now.

If they do a forensic comparison of the photos, just be forewarned there is a cottage industry of "experts" that will authenticate a photographic image as somebody with just the slimmest of evidence, ignoring the larger pile of evidence against it.