The Confederacy was now being so closely pressed in every quarter as to make it impossible, with the forces at its command, to defend effectively and at the same moment every point menaced by the troops and fleets of the Union. Thus the force that might otherwise have been employed in defending New Orleans was, under the pressure of the emergency, so heavily drawn from to strengthen the army at Corinth, then engaged in resisting the southward advance of the combined armies of the Union under Halleck, as to leave New Orleans, and indeed all Louisiana, at the mercy of any enemy that should succeed in passing the river forts. At this time the entire land-force, under Major-General Mansfield Lovell, hardly exceeded 5,000 men. Of these, 1,100 occupied Forts Jackson and St. Philip, under the command of General Duncan; 1,200 held the Chalmette line, under General Martin L. Smith, and about 3,000, chiefly new levies, badly armed, were in New Orleans. Besides this small land-force, the floating defences consisted of four improvised vessels of the Confederate navy, two belonging to the State of Louisiana, and six others of what was called the Montgomery fleet. These were boats specially constructed for the defence of the river, but most of them had been sent up the river to Memphis to hold off Foote and Davis. The twelve vessels carried in all thirty-eight guns. Each of the boats of the river-fleet defence had its bows shod with iron and its engines protected with cotton. This was also the case with the two sea-going steamers belonging to the State. Of this flotilla the most powerful was the iron-clad _Louisiana_, whose armor was found strong enough to turn an 11-inch shell at short range, and, as her armament consisted of two 7-inch rifles, three 9-inch shell guns, four 18-inch shell guns, and seven 6-inch rifles, she might have proved a formidable foe had her engines been equal to their work. At the Plaquemine Bend, twenty miles above the head of the passes and ninety below New Orleans, the engineers of the United States had constructed two permanent fortifications, designed to defend the entrance of the river against the foreign enemies of the Union. These formidable works had now to be passed or taken before New Orleans could be occupied. Fort St. Philip, on the left or north bank, was a work of brick and earth, flanked on either hand by a water battery. In the main work were mounted, in barbette, four 8-inch columbiads and one 24-pounder gun; the upper water battery carried sixteen 24-pounders, the lower one one 8-inch columbiad, one 7-inch rifle, six 42-pounders, nine 32-pounders, and four 24-pounders. Besides these, there were seven mortars, one of 13-inch calibre, five of 10-inch, and one of 8-inch. Forty-two of the guns could be brought to bear upon the fleet ascending the river.