Robert Indiana kept a series of illustrated journals during the late 1950s and 1960s, in which he discusses the development of his work as well as his daily life on Coenties Slip.

In his journal entry for June 17, 1962, Indiana describes working on The Trilogy (The Mellville Triptych): "stenciling “Whitehall” v[ery] carefully and [to] great effect, except that [the] word “the” was off, causing me [to] scrap [the] whole canvas. Since [the] one bearing the cartoon for Coenties Slip is also spoiled for black and white, [this] will have [to] be stretched again, too—reversing me back several days work. But on [this] painting I just can’t accept any such glaring imperfections. So off it was and begin again on [the] third unharmed canvas, [this] time not without some faults, but not bearing [the] blemish of [the] first."

He notes being discouraged, as his gallerist Eleanor Ward's visit would probably be that week.

Indiana also records a visit from Stephen Durkee, who came with a poet friend, who seemed "particularly awestruck by what he saw: surely a premier reaction," and a later visit from Lenore Tawney. Tawney brought over a photographer, Fernando Boesch, who had been taking photographs for her over the past few days. Indiana writes that "he seemed interested in what he saw, and said [that] he might take some color for me. He did not commit himself [to] discuss prices and fees."