Mural was commissioned from Jackson Pollock in 1943, for the entry hall of Peggy Guggenheim’s Manhattan townhouse. Paint seems to stampede the canvas, epic at eight feet high and 20 feet wide. “Every animal in the American West,” Pollock later said, was “charging across that goddamn surface.” Not literally. This masterpiece of abstraction is paired with a newly-commissioned work by Katharina Grosse, a German artist whose hugely-scaled paintings could be described as stampedes of color. —L.J.