Charles Perry Mid Century Interlocking Brass "Ball Puzzle" plan for boat I believe the '69 incised

I believe the '69 incised into the underside along is indeed the year of its making

107-150 + plates) is missing the portfolio cover

I believe it dates to the 1960s or 70s

which I finally purchased after carrying it around with me on two separate visits to a local antique shop

and also large enough to make a nice sculptural object for the wall

Charles Perry Mid Century Interlocking Brass "Ball Puzzle" plan for boat I believe the '69 incisedThis "ball" puzzle, comprised of interlocking solid brass pieces, was designed in 1967 by Charles O. Perry (American 1929 2011), a sculptor and designer best known for monumental structures composed with mathemetical complexity. There is one "key" piece that spring locks into place to complete the puzzle, and will release once one finds it (a bit of trial and error but not hard) to allow one to take it apart. (I have not ventured to do so!) The first