Early in August, Commodore Preble bombarded the town of Tripoli from his mortar boats. During a fight with the gunboats James Decatur, a brother of Stephen, received the surrender of one he was fighting, and stepped on the deck to take possession. As he did so, the captain shot him dead. Stephen had just destroyed a gunboat when he learned of this treacherous occurrence and dashed after the craft, which he boarded. Recognizing the captain from his immense size, he attacked him, and, in a desperate personal encounter, in which he narrowly escaped death himself, killed the Moor. THE BOMB KETCH. The Americans fixed up the _Intrepid_ as a bomb ketch, storing a hundred barrels of powder and missiles and a hundred and fifty shells on deck. Under command of Captain Richard Somers, and accompanied by twelve men, the vessel ran slowly into the harbor one dark night. The intention was to fire a slow-match and then for the officer and men to withdraw in boats. Captain Somers was discovered by the enemy, and in some unknown way the ketch was blown up with all on board, and without doing any material harm to the shipping and fortifications in the harbor. Commodore Preble was superseded in November by Commodore Barron, who arrived with the _President_ and _Constellation_. This gave the Americans ten vessels, carrying 264 guns. Hostilities were pressed with so much vigor that the Dey of Tripoli became anxious to make peace before the terrible fleet from the West destroyed him and his people. Accordingly, a treaty was signed on the 3d of June by which the Tripolitans were given $60,000 for the prisoners in their hands, and the payment of tribute to them was ended. EXPEDITION OF LEWIS AND CLARK. In those comparatively modern days the vast region west of the Mississippi was almost unknown. President Jefferson recommended a congressional appropriation for the exploration of the country. The appropriation being made, a party of thirty men left the Mississippi, May 14, 1804, under command of Captains Meriwether Lewis and William Clark. Both had had a good deal of experience in the Indian country, and they ascended the Missouri in a flotilla for 2,600 miles. To the three streams which form the Missouri they gave the names of Jefferson, Gallatin, and Madison. A detachment was then left in charge of the boats, and the remainder, riding the horses they had captured and tamed, made their way across the mountains. They discovered the two streams which bear their names, and traced the Columbia to its outlet in the Pacific Ocean.