But his [Indiana’s constructions] are not of ubiquitous debris like bicycle parts, driftwood, flatirons, disused plumbing or pieces of junked automobiles. They are redolent of a specific place and of its past, of the buildings which housed a departed and exotic commerce still spelled out in the stencils now on the studio walls, PORTO RICO LINE, OCEANIC COTTON DUCK, N.Y. & CUBA MAIL S.S. CO. The age and time that sits upon this material dragged out of the past is told explicitly in Hub: its wheel like a wheel of change or an ancient time clock, its spokes precisely subtending a number series which counts the passage of hours or decades. In these objects, which were more just there on the waterfront than “found,” Indiana found the means to express his fascination with time and history.
— John McCoubrey
"Introduction," in John McCoubrey and Robert Indiana, Robert Indiana (Philadelphia: Institute of Contemporary Art and Falcon Press, 1968), p. 12.