I like saying it over and over. Some words are like that. It certainly adds interest to Poe's poem. And, yes, there is such a word. One cannot miss his repetition of words.
Repetition is another device poets use.
But know it is true if you trust, The tears you shed now in such sorrow Will be tears of great joy on the morrow. Unusual or little used words can be used to great advantage, but how words are put together is also important. And that's one of the great differences between poetry and prose. He certainly woudn't last long at an editorial desk. We'll be coming across this thought a number of times in the course of our writing.