[2] Blue mass was recommended as a remedy for such widely varied complaints as tuberculosis, constipation, toothache, parasitic infestations, and the pains of childbirth.
"[3] A combination of blue mass and a mixture called the common black draught was a standard cure for constipation in early 19th century England and elsewhere.
It was particularly valued on ships of the Royal Navy, where sailors and officers were constrained to eat rock-hard salted beef and pork, old stale biscuits (hardtack), and very little fruit, fiber, or other fresh food once they were at sea for an extended period.
[5] It's been reported that during this time, Lincoln was known to have experienced neurological symptoms, including insomnia, tremor and rage attacks, which suggests he may have been suffering from mercury poisoning.
[5] In 2001, a study led by renowned public-health investigator Norbert Hirschhorn recreated a typical formulation,[6] concluding that the quantity of blue mass that Lincoln likely took would have delivered "a daily dose of mercury exceeding the current Environmental Protection Agency safety standard by nearly 9000 times,"[5] which may have adversely affected his health.