Since writing "Vintage Plastic Sliding-Letter Puzzles" (WW, Nov. 2011, p.310) I have discovered some additional puzzles of ths kind manufactured by various companies during the 1960's and 1970's -and one of the recent vintage that is still in print. In this article I will describe these puzzles and discuss some of the logological problems suggested by them.
"More Sliding-Letter Puzzles,"
Word Ways: Vol. 45
, Article 5.
Available at: http://digitalcommons.butler.edu/wordways/vol45/iss1/5