How does Seamus Heaney use imagery in The Singer's House?

In addition to relying on symbols to point out the subtext of the poem, Heaney also creates a number of images, most of which are generated in his mind. The reader follows Heaney on this journey through his memory and thoughts of the present and future, starting with the first reference to "Carrickfergus." Heaney tells the reader that a past conversation involving the city made him imagine the "frosty echo of saltminers' picks." During this first stanza, Heaney gives the sound of these picks a physical form, shaping it into an image of "a township built of light," words that are meant to evoke a positive image in the reader's mind. Heaney's mental images reach a higher level of detail after he says "Gweebarra." In this new place, in the present, he formulates his argument to Hammond to sing again. Heaney pulls Hammond, and the reader, into an increasingly complex image, each line adding another detail. Like the first stanza, it starts with a sound, "water hitting off granite." From there, Heaney follows the physical manifestation of this "glittering sound" as it travels to a window, then down to the beach where the "seals' heads, suddenly outlined" are "scanning everything." Finally, in the future that Heaney imagines could take place if Hammond sings again, the singer stands "in the mouth of a whitewashed turfshed," sending his song out like "a rowboat far out in evening," two vivid images.