_Aaron Burr_, the Vice-President, was Alexander Hamilton's bitter rival, both in law and in politics, and at last challenged him to a duel. Hamilton accepted. The affair took place at Weehawken (July 11, 1804). Hamilton fell at the first fire, on the very spot where his eldest son had been killed shortly before, in the same manner. His death produced the most profound sensation. Burr afterward went west and organized an expedition with the avowed object of forming a settlement in northern Mexico. Being suspected, however, of a design to break up the Union and found a separate confederacy beyond the Alleghanies, he was arrested and tried (1807) on a charge of treason. Although acquitted for want of proof, he yet remained an outcast. [Footnote: While awaiting his trial, Burr was committed to the common jail. There, among its wretched inmates, stripped of all his honors, lay the man who once lacked but a single vote to make him President of the United States.] [Footnote: Closely connected with Burr's conspiracy is the romantic story of Blennerhassett. He and his beautiful wife. Having settled on an island in the Ohio Kiver, they had transformed the wilderness into a garden of beauty, and every luxury and refinement which wealth or culture could procure clustered about their homes. Into this paradise came Burr, winning their confidence, and engaging them in his plans. On his downfall, Biennerhassett as arrested. When finally acquitted everything had been sold, the grounds turned into a hemp field, and the mansion into a store-house.] _Fulton's Steamboat_.--The year 1807 was made memorable by the voyage from New York to Albany of Robert Fulton's steamboat, the Clermont. For years the Hudson could boast of having the only steamboat in the world. [Illustration: THE FIRST STEAMBOAT] FOREIGN AFFAIRS.-- _War with Tripoli_.--The Barbary States, of which Tripoli is one, for many years sent out cruisers which captured vessels of all Christian nations, and held their crews as slaves until ransomed. The United States, like the European nations, was accustomed to pay annual tribute to these pirates to secure exemption from their attacks. The Bashaw of Tripoli became so haughty that he declared war (1801) against the United States. Jefferson sent a fleet which blockaded the port and repeatedly bombarded the city of Tripoli. The frightened Bashaw was at last glad to make peace. [Footnote: During this blockade a valiant exploit was performed by Lieutenant Decatur. The frigate Philadelphia had unfortunately grounded and fallen into the enemy's hands. Concealing his men below he entered the harbor with a small vessel which he warped alongside the Philadelphia, in the character of a ship in distress. As the two vessels struck, the pirates first suspected his design. Instantly he leaped aboard with his men, swept the affrighted crew into the sea, set the ship on fire, and amid a tremendous cannonade from the shore escaped without losing a man.]