One could argue that the midcentury American sculptor Herbert Ferber is the father of the site-specific work. His 1961 Sculpture as Environment (it’s now called Environment for Sculpture), created for the Whitney Museum, was a large-scale form that allowed the viewer entrance into its expression—an installation! The small exhibition now on in Philadelphia brings together 20 sculptures and drawings that argue for the importance of Ferber. As the art critic Eric Gibson recently wrote in The New Criterion, Ferber “made line alone the sufficient condition of sculptural expression, endowing it with an energy and a range of reference and association unique in sculpture up to that time. . . . Line simultaneously occupies, creates, and energizes space.” —L.J.