I recently acquired this stamp and have no idea if it is just a cancellation or an Internal Revenue overprint. Has anyone seen a stamp like this in the past?
Well, that's interesting. I would venture it's an attempted overprint "I R" for Internal Revenue. They did try to generate tax revenue because of the Spanish American war, and correctly this is a Bureau issue ( likely a 264 ). Scotts Specialized documents an "a" and "b" type, but the fonts are not these on the stamp. Also, there is no period after the letters ( a-type is square, b type is round). Perhaps it's a local provisional revenue stamp produced by some rural postmaster? ( they did that back in the day). But it does not appear to be a cancel as the adjacent black ink does appear to be of slightly different hue.
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