On August 14, 1834, he departed Boston aboard the brig Pilgrim, captained by Frank Thompson, bound for Alta California, at that time still a part of Mexico.

After witnessing Thompson's sadistic practices, including a flogging on board the ship, he vowed that he would try to help improve the lot of the common seaman.

Dana became a prominent abolitionist, helping to found the anti-slavery Free Soil Party in 1848 and representing the fugitive slave Anthony Burns in Boston in 1854.

During the American Civil War, Dana served as a United States Attorney, and, in the Prize Cases, successfully argued before the Supreme Court that the U.S. president had the power under the U.S. Constitution to blockade Confederate ports.

On August 24, 1868, Dana wrote a letter to Attorney General William Evarts arguing that the United States should abandon the prosecution because, even though there was no doubt that Davis had committed treason, a jury in Virginia would be unlikely to convict, which "would be most humiliating to the Government and people of this country."

[17] In 1876, his nomination as minister to Great Britain was defeated in the Senate by political enemies William Beach Lawrence and Benjamin Butler, partly because of a lawsuit for plagiarism brought against him for a legal textbook he had edited, Henry Wheaton's Elements of International Law (8th ed., 1866).

[18] Immediately after the book's publication, Dana had been charged by the editor of two earlier editions, William Beach Lawrence, with infringing his copyright, and was involved in litigation that continued for thirteen years.

[19] In 1877, Dana was one of the counsel for the U.S. federal government, appearing before the Halifax Fisheries Commission, appointed under the Treaty of Washington (1871) to resolve outstanding issues, including fishing rights.

Towards the end of his life he went to Europe to devote himself to the preparation of a treatise on international law, but the actual composition of this work was little more than begun when he died in Rome, January 6, 1882.

He came of a stock that had resided there since the days of the early settlements; his grandfather, Francis Dana, had been the first American minister to Russia and later became chief justice of the Supreme Court of Massachusetts; his father was distinguished as a man of letters.

Tired of the tedium of a slow convalescence, he decided on a sea voyage; and choosing to go as a sailor rather than a passenger, he shipped from Boston on August 14, 1834, on the brig Pilgrim, bound for the coast of California.

His experiences for the next two years form the subject of the present volume.In the December following his return to Boston in 1836, Dana re-entered Harvard, the hero of his fellow students, graduating the following June.

After several years of practicing law, during which he dealt largely with cases involving the rights of seamen, he began to take part in politics as an active member of the Free Soil Party.

Three years later, his health gave way from overwork, and he set out on a voyage round the world, revisiting California, where he made the observations that appear in the postscript to this book.

In his argument before the U.S. Supreme Court in the Prize Cases, which upheld Lincoln's blockade of Southern ports, he greatly increased an already brilliant legal reputation.