|Maps upon this website are in the public domain because they are mechanical scans of public domain originals, or - from the available evidence - are so similar to such a scan or photocopy that no copyright protection can be expected to arise. The originals themselves are in public domain for the following reason:
This tag is designed for use where there may be a need to assert that any enhancements (eg brightness, contrast, colour-matching, sharpening) are in themselves insufficiently creative to generate a new copyright. It can be used where it is unknown whether any enhancements have been made, as well as when the enhancements are clear but insufficient. For usage, see Commons:When to use the PD-scan tag.