"Large and without mercy" is a pretty good description of the disorienting effect of Sequence—one of three immense new works in the second-floor gallery at MoMA—on anyone braving its labyrinthine corridors. As the torqued walls shift from concave to convex, you may begin to sense that the floor is moving; the funhouse experience can make you seasick. In these enter-at-your-own-risk structures, Serra is pushing the boundary between sculpture and architecture; he is shaping space as much as creating objects. Serra has described these new works as "vessels that you walk into," sounding a deep pun on the nature of "vessels"—as both ships and pottery. The soft orange surface of the weatherproof steel recalls terra cotta, and Serra has looked to the history of ceramics, with its coils and pottery wheels, for analogies for these twisted elliptical forms. At the same time, the nautical impression, as of beached battleships, has intensified.