Escher’s mature style emerged after 1937 in a series of prints that combined
meticulous realism with
enigmatic optical
illusions. Working in
lithograph,
wood engraving, and woodcut, he portrayed with great technical virtuosity impossible architectural spaces and unexpected
metamorphoses of one object into another. Sometimes referred to as the “father of modern tessellations,” Escher commonly used geometric grids to form intricate interlocking designs. His series
Regular Division of the Plane (begun in 1936) is a collection of his tessellated drawings, many of which feature animals. He also explored
mezzotint, a demanding and precise technique involving metal engraving, with which he produced some of his famous works in black and white, including
Eye (1946),
Gallery (1946),
Crystal (1947), and
Dewdrop (1948). In all, Escher composed some 450 lithographs, woodcuts, and wood engravings and about 2,000 drawings and sketches in his lifetime. His images were of equal interest to mathematicians,
cognitive psychologists, and the general public, and they were widely reproduced throughout the 20th century.