One variation of clay animation is strata-cut animation, in which a long bread-like loaf of clay, internally packed tight and loaded with varying imagery, is sliced into thin sheets, with the camera taking a frame of the end of the loaf for each cut, eventually revealing the movement of the internal images within. Pioneered in both clay and blocks of wax by German animator Oskar Fischinger during the 1920s and 1930s, the technique was revived and highly refined in the mid-1990s by David Daniels, an associate of Will Vinton, in his 16-minute short film "Buzz Box".