Jeannette sank in June 1881; a few months later, when asked either to stay or depart with two crewmen, he decided to remain aboard and provide medical attention to those alive.

[6] At the age of sixteen, Ambler volunteered in the 12th Virginia Cavalry Regiment and served during the late months of the American Civil War.

[8] After graduating in 1870, Ambler became a clinical recorder at the University of Maryland Medical Center and later an assistant physician at the Quarantine Hospital in Baltimore, before entering private practice with J. G.

[11] Ambler prepared with studies of previous expeditions, consulted specialists at the Smithsonian Institution, and made visits to the Johns Hopkins University.

[13] After Ambler discovered that some of the crew had gotten lead poisoning due to the canned tomatoes, he treated them for stomach cramps and relating symptoms.

[12] The ship sank on June 13, 1881,[8][a] Ambler looked after the sick crew while on the 300 miles (480 kilometers) journey across an ice-covered landscape, with the goal of finding open sea.

[9][12] On October 8, 1881, after the food supplies were exhausted, De Long gave Ambler the decision to either stay or depart with the two strongest crewmen who eventually reached safety and passed command on to him.

[16] In his book In the Lena Delta (1885), Melville wrote of Ambler that he "proved himself a skilled physician, an excellent officer and a noble man.

"[8] The author Christopher J. Huggard wrote that Ambler's efforts made Jeannette the first arctic expedition "without a single case of scurvy".