One major similarity between H.D.'s two poems "Oread" and "The Pool" is that both pieces involve a speaker actively engaging with the natural world, specifically with bodies of water. In "The Pool," we get the sense of a speaker either contemplating the nature of a pool of water itself ("What are you - banded one?" (5)), or something lying within a pool of water. In "Oread," we encounter a speaker forcefully addressing the tumultuous waves of an ocean, comparing them to falling pine trees. In both poems, it seems like the speaker is engaging with and defining bodies of water in some fashion.
The major difference between the two poems is tone. While "Oread" has a forceful quality that implies the speaker is actively controlling a tempestuous sea, "The Pool" is quieter and more contemplative, and, in some ways, more unsettling. That opening question "Are you alive?" (1) brings to mind the image of a corpse, and so the poem's quiet interrogation of its subject is much more menacing than the exuberant action of "Oread."