Mapping used to be my business, mon. I'm probably the only participant here who knows what you're talkin'bout when you reference stuff like NAD27. Been out of it for more than a decade now, but still love the intense information concentration of maps and the incredible views of the planet from above.
My fave map in my meager collection is a pocket map of the NY 'wilderness' published by Colton in 1879. I paid ten bucks for it thirty years ago and just noticed that a copy had sold on Ebay for $395!
http://www.ebay.com/itm/1879-COLTON-POCKET-MAP-NEW-YORK-WILDERNESS-RARE-/220761996580
Of course, as a map of 'wilderness' it's devoid of much detail, but that essential contradiction is what gives the piece its interest for me.
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