“Relativity”: Lithograph print, first printed in December 1953. In the world of Relativity, there are three sources of gravity, each being orthogonal to the two others.
Each inhabitant lives in one of the gravity wells, where normal physical laws apply. There are sixteen acharacters, spread between each gravity source, six in one and five each in the other two. The apparent confusion of the lithograph print comes from the fact that the three gravity sources are depicted in the same space.
“Birds”: Plane-filling Motif with Birds, wood engraved 1949. M.C. Escher often created complex interlocking designs with animals such as birds, fish, and reptiles.