Contest sets must have been popular in the 1930's, based on number of cutters who made them. This lovely set of 4 puzzles was cut by Burton J. Maddox of Jamestown, NY, whose logo was an ink stamp on the back of his puzzles, of the words "maddox" in the form of a figure of a mad ox. Interestingly, Maddox stack cut all 4 puzzles at same time (one on top of each other) so as to make puzzles identical in their cut. This also results in pieces in the same location of each puzzle being interchangeable from one puzzle to the next. However, it does not achieve the same degree of difficulty for all 4 puzzles; the picture has something to do with that. As you can imagine, 2 puzzles on left will take longer to assemble than 2 on right. Artists are: Fox, Goodwin, Schenck, and Dahl.