For instance, the first time the ship comes across sperm whales, the type of whale they are hunting, Ishmael says, ". . . neither of those can feel stranger and stronger emotions than the man does, who for the first time finds himself pulling into the charmed, churned circle of the hunted sperm whale."
The repetition of the st sounds in "stranger" and "stronger" and the repetition of the ch sounds in "charmed" and "churned" contributes to the sense of drama in the moment ("churned" also resonates, through assonance, with the word "sperm,").
See examples of assonance, or return to more examples of alliteration.
