The Rhyme
Based upon the lines you have provided, it is important to note that the word “light” is never mentioned not even just one time. However, the last word of the second line and the last word of the third line, there are the words “sight” and “midnight.” And, both of these words rhyme with “light.” As such, it is through clever use of rhyme in this stanza you have provided that Emily Dickenson is able to connect the concepts of light and dark with never even mentioning the word “light.”