How did White-Jacket criticize conditions in the U.S. Navy?

In his 1850 novel White-Jacket, Herman Melville drew upon his personal experiences as a seaman to expose the harsh realities of life aboard a U.S. Navy frigate. The book served as a powerful critique of the service in two primary ways:1

• Corporal Punishment: The novel provided a compelling argument against the use of flogging as a disciplinary measure. Its publication coincided with congressional debates on the subject, and copies of the book were distributed to members of Congress to influence their decision-making. Flogging in the U.S. Navy was subsequently abolished that same year.1
• Systemic Tyranny: Subtitled The World in a Man-of-War, the narrative detailed the oppressive environment aboard the ship Neversink. Melville highlighted the "tyrannies" imposed by officers upon ordinary sailors and described the "appalling conditions" under which the crew was forced to live.1

By documenting these abuses, White-Jacket garnered significant political support and became a landmark work of social criticism within American literature.2