If your looking for large collections of high-resolution antique maps, books, documents and similiar items, check out YourMapsOnline.org.uk. and YourOldBooksAndMaps.co.uk.
They have Mac friendly versions of all of their CDs (the materials come in standard Adobe Acrobat (PDF) and graphic formats).
Although it’s mostly oriented towards the UK, they do have materials from around the world. You can sample the maps , books, etc., on their website for free. Among the materials: Trade Directories, Maps & Atlases, County History & Topography Books & Old Travel Books.
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