Fort Henry and its approaches were reconnoitered on the 21st January by the United States gunboat Lexington, with a view to ascertain its strength and the position of the rebels. She went within two miles of the fort, and flung a number of shells into it without eliciting any reply. At first it was thought the rebels had evacuated the work, but on approaching it still nearer pickets were discovered at various points. The heavy guns on the work were seen distinctly; also a number of field pieces. In addition to the fort proper, numerous earthworks had been thrown up on a high bluff above the fort, on the west bank of the river. This additional work, named Fort Hieman, commanded Fort Henry. On the 22d January, Brigadier-General C. F. Smith, commanding the second division of General Grant’s army, was at Crown Point, Ky., where he had arrived with 6,000 men after a fatiguing march of over 100 miles from Paducah. He proceeded thence on a personal reconnoissance, on the gunboat Lexington, in the direction of Fort Henry. The gunboat advanced up the west channel of the river to a point within one mile and a half from the fort. General Smith obtained an excellent view of the rebel fort, camp and garrison, and sent his report to headquarters. He then marched his division back to Paducah. The flotilla of gunboats, which had been so long in course of preparation on the Ohio and Mississippi, was now ready to take part in the impending battles of the nation, and to assume that prominence in the momentous events which were to follow to which they have proved themselves justly entitled. Flag-officer Andrew H. Foote was appointed by the Government to command the naval forces on the Upper Mississippi and the Western waters, and now led forth his gallant fleet to attack the enemy, in conjunction with the land forces under General Ulysses S. Grant. The fleet consisted of _Fleet Officers._—Flag-Officer Andrew H. Foote; Fleet Captain, Commodore A. M. Pennock; Ordnance Officer, Lieutenant J. F. Sanford; Ordnance Lieutenant, Byron Wilson; Flag Lieutenant, James M. Prickett. _Essex_, 9 _guns_, Commander William D. Porter. _St. Louis_, 13 _guns_, Lieutenant-Commanding Leonard Paulding. _Cincinnati_, 13 _guns_, Commander R. N. Stembel. _Carondelet_, 13 _guns_, Commander Henry Walke. _Conestoga_, 9 _guns_, Lieutenant-Commanding —— Phelps. _Tyler_, 9 _guns_, Lieutenant-Commanding W. Gwin. For several days, at Paducah, the utmost vigilance was exercised at the headquarters of the Provost Marshal, in issuing passes, and on Sunday and Monday, the 3d February, no persons were allowed in or out of the lines. Half a dozen gunboats steamed leisurely into port and brought their black forms to anchor opposite the levee, in the centre of the river.