Emerson uses a simile to compare the youthful joy of being in the wilderness to a snake that is shedding its skin:
In the woods too, a man casts off his years, as the snake his slough, and at what period soever of life, is always a child.
By making this comparison, Emerson highlights the rejuvenating power of the natural world. Snakes are oftentimes associated with medicine and eternal life. For example, the Rod of Asclepius, which in Greek mythology is the staff that belongs to the god of healing and a modern symbol associated with medicine, is recognizable for the snake(s) that wrap around it. In the Sumerian tale The Epic of Gilgamesh, the phenomenon of snakes shedding their skin is explained with the story of one snake stealing a plant that grants eternal life. Thus, by invoking the shedding snake, the simile expresses that the woods are a place of healing, in which the mythic wonder of eternal youth can be found.
Additionally, it is no accident that Emerson compares the feeling of being in nature to an animal that exists in nature. Emerson could have chosen to invoke a man-made or divine image to compare the feeling with, but he uses an image from the natural world instead. Later, in the chapter about language, he asserts that all abstract language comes from the natural world and that acknowledging that fact reveals a certain purity of thought. The simile is an example of using the natural world to relate to and better understand human concepts, a practice that Emerson encourages and praises.
Emerson uses a simile to compare riding on a railroad to the flight of a bird. In doing so, he expresses the freedom and intelligence that humans have in the age of industry:
To diminish friction, he paves the road with iron bars, and, mounting a coach with a ship-load of men, animals, and merchandise behind him, he darts through the country, from town to town, like an eagle or a swallow through the air.
Birds are often associated with a number of symbolic meanings. They are a common symbol of freedom, due to their ability to fly easily and unconstrained. Emerson, by comparing railway riders to birds, demonstrates the freedom that railroads grant humanity. Before, distances that would have taken far longer when traveled by horse and cart can be quickly traversed by rail. This power gives humanity much more mastery over the natural world than in past ages.
What's more, eagles are often considered symbols of power. They have been used by governments from Rome to the United States to signify nobility and strength. They are invoked in a similar way here, demonstrating that railways grants humanity power.
The swallow, on the other hand, is a small and delicate migratory bird capable of traveling large distances. Emerson likely invokes the swallow to emphasize that the distances that can be traveled by trains are impressive. Trains essentially allow humans to behave like migratory birds, traveling long distances to suit their needs.
The simile that Emerson employs, in which he compares nature to the Saviour's ass, is meant to highlight the importance of nature while also setting it up in a subservient relationship to man:
[Nature] receives the dominion of man as meekly as the ass on which the Saviour rode.
According to the Torah or the Old Testament, the prophet Zechariah wrote that a king would come to the people upon an ass. Riding an ass is fairly standard symbolism for a savior figure, as in the Book of Kings when the legendary King Solomon rides an ass to his God-ordained coronation. So, in the New Testament, when Jesus rides an ass into Jerusalem, he is recognized as the messiah instantly, and the people rejoice.
In the story, the ass is necessary for Jesus's recognition as messiah, just as nature is necessary for man’s health and wellbeing, even if it is in a role of service. This characterization does not necessarily diminish the divinity of nature that Emerson spent so much time establishing, as the service of the ass is not debasing, it is essential. To Emerson, being used is not a sign of something being disposable but rather a sign of something being good.
Using a simile to compare nature to the figure of Jesus, Emerson again emphasizes its divine aspects:
The aspect of nature is devout. Like the figure of Jesus, she stands with bended head, and hands folded upon the breast.
Nature, here, like Jesus, both worships and is divine. Emerson suggests that devotion is something that can be learned from nature, but he also indicates that people should be devoted to nature. Devotion can be learned from nature because Emerson believes that all nature is molded in accordance with the divine spirit and moral law. By looking at the way that nature bends itself to God’s will, one can learn the humility necessary for worship. But nature, having both divine spirit and moral law in it, is also worthy of worship.
To some, this may seem like a contradiction, especially since Emerson previously called nature the ass on which Jesus rode, and now he’s calling nature Jesus itself, but the dual similes are supposed to demonstrate how nature simultaneously gives glimpses of the divine and teaches one humility.
In Emerson’s eyes, just as Jesus was both God and a sacrifice himself, so too is the natural world. Nature should serve both as a good in itself and as something that is good because of what it produces. Nature, then, is meant to both serve and be served. One should be reverent toward nature but also recognize that it is meant to serve.
