The New York Times this morning, in an
obituary for a maker of crossword puzzles :
"… the first known crossword puzzle appeared in
an American newspaper. (Called a 'word-cross'
and shaped like a diamond, it was published in
The New York World on Sunday, Dec. 21, 1913.)"
See St. Nicholas magazine, November 1874, p. 59 :
For the answer, see this journal on Aug. 29, 2002
(with a scene from Spellbound ) and on July 15, 2004.