Read it through once

The next desideratum was a pretext for the continuous use of the one word “Nevermore.” In observing the difficulty which I at once found in inventing a sufficiently plausible reason for its continuous repetition, I did not fail to perceive that this difficulty arose solely from the pre-assumption that the word was to be so continuously or monotonously spoken by a human being—I did not fail to perceive, in short, that the difficulty lay in the reconciliation of this monotony with the exercise of reason on the part of the creature repeating the word. Here, then, immediately arose the idea of a non-reasoning creature capable of speech; and, very naturally, a parrot, in the first instance, suggested itself, but was superseded forthwith by a Raven, as equally capable of speech, and infinitely more in keeping with the intended tone.