Rhetorical devices refer to a means in which an author uses language to better convey meaning and persuade the reader to favor the author's opinion. Many different rhetorical devices exist, including aphorism, allusion, contradiction, syllogism, and many others (University of Kentucky, Glossary of Rhetorical Terms).
Parallelism is also a common rhetorical device. Parallelism is constructed when a writer creates patterns in wording, grammar, and sentence structure in order to create clarity and emphasis. There are many different types of parallelism, and all throughout the book Silent Spring, author Rachel Carson uses a great deal of subtle parallelism to persuasively argue her points.
One example of parallelism found in the chapter titled "The Obligation" can be referred to as anaphora. Anaphora is created when an author repeats words in the beginning of clauses. Dr. Wheeler provides us with the famous example spoken by Churchill: "We shall not flag or fail. We shall go on to the end." (Carson-Newman University, "Schemes")
In Carson's second chapter, we can see an example of anaphora in the following sentence concerning radiation:
Radiation is no longer merely the background radiation of rocks, the bombardment of cosmic rays, the ultraviolet of the sun that have existed before there was any life on earth; radiation is now the unnatural creation of man's tampering with the atom. (p. 7)
Since Carson deliberately starts both her first and second independent clauses with the words "radiation is," we can see how the repetition in this sentence creates a perfect, though subtle, example of anaphora. Moreover, Carson uses no conjunctions, not even a final conjunction, in her list pertaining to radiation, which is also a perfect example of a parallelistic structure, or rhetorical device, called asyndeton.
In addition, throughout her work, Carson craftily makes use of the rhetorical appeals logos, ethos, and pathos, and one can also find examples of literary devices like figurative language, especially personification (Durham Technical Community College, "A General Summary of Aristotle's Appeals"; Dr. Wheeler, "Tropes").