With its faceted sides and modular composition, Tony Smith’s Source is synchronously geometric and organic. The large-scale sculpture, fabricated in steel and painted in the artist’s characteristic black, was conceived in 1967. An unfolding of form, Source is exemplary of what Smith referred to as ‘ presences’. There is a physical immediacy in its balance of mass and volume and its unexpected transformation of form. Its obvious weight produces a visceral effect for the viewer, perpetuating its presence in the surrounding space. Smith’s experience in architecture informed his conceptions of space and scale, and his innovations in sculpture – though radical – were natural responses for him. These include having his work industrially fabricated, a method he introduced in 1962, and his use of modular systems to create sculpture. Influenced by Alexander Graham Bell’s application of standardized units in his kites and structures, Smith began to explore the potential of the tetrahedron and octahedron as compositional elements. In its dynamism, Source, made up of tetrahedrons and octahedrons, speaks to the plasticity and visual continuity that Smith achieved when working within this system of organization.