In 1761 The first American life insurance policy was issued in Philadelphia. In 1785 Benjamin Franklin invented the first bifocals. In 1807 Former vice president Aaron Burr was imprisoned for treason in Richmond, VA, but was acquitted in September. In 1819 The first steamship to cross the Atlantic, the Savannah, departed from Savannah, Georgia, and arrived in Liverpool 29 days later. In 1843 The first wagon train left Independence, MO, for the Oregon Trail. In 1856 Violence erupted in Congress when Rep. Preston S. Brooks whacked Senator Charles Sumner with a cane. In 1868 The "Great Train Robbery" takes place in Indiana when seven men hold up the crew, detach the locomotive, and seize $96,000 in cash, gold, and bonds. In 1888 Leroy Buffington patented 1939, Adolph Hitler, and Benito Mussolini signed the "Pact of Steel," committing Germany and Italy to a military alliance. In 1947, Congress enacted The "Truman Doctrine" with economic aid for Greece and Turk