Mouth (symbol)
It’s significant that the one time the speaker departs from the refrain “and I am dumb to tell,” which otherwise occurs in every stanza, the verb is replaced with “mouth.” Mouths show up repeatedly in the second stanza, from the “mouthing streams” that are dried out over time to the “mouth” of time “suck[ing]” at the spring itself. In the fourth stanza, mouths reappear, with the “lips of time” again sucking at a waterlike image (“the fountain head”). In this manner, Thomas expresses a union between time—which is like a mouth as it “leech[es]” at life; humans—who mouth to try to express their thoughts; and nature—in the form of the river, which "mouths" as it flows.
Water (symbol)
Water is one of the most common symbols in poetry, often representing life. The speaker likens the water flowing in the river to the flow of his blood, which sustains his life; quicksand, which has the power to take life; and again blood from the “fountain head” where love bleeds. Like time, water is thus associated with both life and death. These associations deepen in the third stanza, where water, which embodied life in the previous stanza, now presents a deadly danger in the form of a whirlpool and quicksand. In this manner, water emerges as both a creative and a destructive element.
Nature (symbol)
Throughout the poem, various aspects of nature are used to represent the human body and its life processes. By drawing on such images, Thomas illustrates the interdependence of humanity and nature and the way in which both are linked through the passage of time. The human body serves as a microcosm of nature as a whole, which has both bleak and hopeful implications. On one hand, humans are doomed to die just as every other natural thing does. Yet nature itself continues to live, constantly replicating itself in new microcosms.
