Changes

His transformation pictures feature regular, repeating patterns of objects which change and transform, row by row or column by column. For example, in ''Sky and Water,'' rows of birds start out as realistic and detailed. In successive rows, the birds become less realistic, more stylized, and more vague, and gradually transform themselves into empty spaces between rows of fish at the bottom of the page. Meanwhile, the empty spaces between the birds gradually become more and more fish-shaped and transform themselves into solid fish.

His transformation pictures feature regular, repeating patterns of objects which change and transform, row by row or column by column. For example, in ''Sky and Water,'' rows of birds start out as realistic and detailed. In successive rows, the birds become less realistic, more stylized, and more vague, and gradually transform themselves into empty spaces between rows of fish at the bottom of the page. Meanwhile, the empty spaces between the birds gradually become more and more fish-shaped and transform themselves into solid fish.

One of his most elaborate transformation pictures, ''Metamorphosis,'' is only nine inches high but over thirteen feet long (and difficult to frame!). A square pattern made from the word "Metamorphose" is transformed successively into a chessboard, lizards, hexagons, a beehive, bees, birds, fish, a rhombic pattern, a town (specifically Atrani, in Italy), then a chessboard with pieces (the rook on the chessboard is also a tower from Atrani's fortifications), and back again to the words "Metamorphose."

One of his most elaborate transformation pictures, ''Metamorphose II'' is only nine inches high but over thirteen feet long (and difficult to frame!). A square pattern made from the word "Metamorphose" is transformed successively into a chessboard, lizards, hexagons, a beehive, bees, birds, fish, a rhombic pattern, a town (specifically Atrani, in Italy), then a chessboard with pieces (the rook on the chessboard is also a tower from Atrani's fortifications), and back again to the words "Metamorphose."

Some of his graphics are beautifully elaborated "impossible figures." ''Ascending and Descending'' shows a building with an impossible staircase forms a connected rectangle. One row of monklike figures traverses the stair in a clockwise direction, always ascending, yet always returning to the same place, while another row traverses the same stairs in a counterclockwise direction, always descending, yet always returning to the same place.

Some of his graphics are beautifully elaborated "impossible figures." ''Ascending and Descending'' shows a building with an impossible staircase forms a connected rectangle. One row of monklike figures traverses the stair in a clockwise direction, always ascending, yet always returning to the same place, while another row traverses the same stairs in a counterclockwise direction, always descending, yet always returning to the same place.