There is a page bound inside the PROPAEDIA Outline of Knowledge, Guide to the Britannica that says....."This special edition of Encyclopaedia Britannica entitled the Constitution Edition is limited...
It was first printed in 1768.
probably a lot. it's more than a century old. that's just a guess though. check with a professional, or go on the antique warehouse show! haha :)
Yeah it is go check in stores.
New Edition was form in 1978