One poem that does appear to be a literal transcription of a visual experience is "Young Sycamore" (1927). As Dijkstra has shown, it is probably based on a photograph by Stieglitz entitled "Spring Showers." Dijkstra praises the poem as a literal record of the eye's "linear movement" as it takes in the photograph. A second reading, however, will show that the poem is hardly without personification or metaphor, although they are implied rather than stated. Williams hints that Stieglitz' sycamore is also a tree of life, starting with youth's "round and firm trunk" and then "waning" gradually until the branches are "bending forward" like the bodies of the old; Both men and trees have offspring: seed "cocoons" hang from the leafless branches. The eye’s movement thus merges with the inner eye’s vision of time’s passage.
From "Some Versions of Modernist Pastoral: Williams and the Precisionists." Contemporary Literature 21:3 (1980), 383-406.