Whitman was bored by the lecture and left. He had no interest in astronomy. He wandered off (probably homeward). At this time, the middle 1800s, street lighting was almost non-existent, and if outside its feeble light it was pitch darkness. The streets and roads were unsealed, with potholes, some filled with muddy water and there were few footpaths. He may have carried a lantern so that he could see exactly where he was putting his feet but in looking for good footing in that dim light he would soon lose his way. So what did he do to navigate? He tells us that he "from time to time, looked up in perfect silence at the stars."