When Walt Whitman was sitting in a Lecture by a well respect professor he noticed something. When he saw the proofs, and figures before him he realized something. When he was forced to decipher the charts and diagrams and how to add, divide, and measure them he became tired and distraught. As Wilt looked up in the night sky a blanket of warmth and comfort draped over him and he had a epiphany. Throughout, his time with this well respected professor nothing come compare to the knowledge learned from nature.
In the beginning of the poem he tells about the tedious challenges he had to do as he was listening to the professor. He gives examples like, adding and dividing the charts and diagrams he was given. He doesn't us much illustration in the beginning to capture the dullness of the environment. During the end, however, he uses very descriptive words to capture the beauty of nature. Phrases like "mystical moist night-air" and "Perfect silence at the stars" are the punctuation mark to this very spiritual poem. Walt Whitman does an exemplary job by capturing how lacking the knowledge from a professor is to knowledge from Nature itself.