On the 20th instant, the army commanded its march, having landing the previous day without opposition: on the 21st it reached Nottingham, and on the 22nd moved on to Upper Marlborough, a few miles distant from Pig Point on the Patuxent, where Admiral Cockburn fell in with and defeated the flotilla taking and destroying the whole. Having advanced to within 16 miles of Washington, and ascertaining the force of the enemy to be such as might authorize an attempt at carrying his capital, I determined to make it, and accordingly put the 1200 men appeared to oppose us but retired after firing a few shots.

On the 24th the troops resumed their march, and reached Bladensburg, a village situated on the left bank of the eastern branch of the Pofowmac, about five miles from Washington. On the opposite side of that river the enemy was strongly posted on very commanding heights formed in two lines, his advance occupying a fortified house, which, with artillery, covered the bridge over the eastern branch, across which the British troops had pass. A broad and straight road, leading from the bridge to Washington ran through the position, which was carefully defended by artillery and riflemen. The disposition for the attack being made, it was commenced with so much impetuosity by the list brigade, consisting at the 85th light infantry and the army, under the command of Col. Thornton, that the fortifired house was shortly carried, the enemy retiring to the higher grounds. In support of the light brigade I ordered up a brigade under the command of Col. Brooke, who with the 44th regiment, attacked the enemy's left, the 4th regiment pressing its right with such effect as to cause him to abandon his guns. His first line giving way, was driven on the second, which, yielding to the irresistible attack of the bayonet, and the well directed discharge of rockets, got into confusion and fled. The rapid flight of the enemy, and his knowledge of the country, precluded the possibility of many prisoners being taken, more particularly as the troops had, during the day, undergone considerable fatigue.

The enemy's army amounting to 8 or 9000 men, with 3 or 400 cavalry, was under the command of Gen. Winder, being formed of troops drawn from Baltimore and Pennsylvania. His artillery, ten pieces of which fell into are hands, was commanded by Com. Barney, who was wounded and taken prisoner. The artillery I directed to be destroyed. Having halted the army for a short time, I determined to march upon Washington, and reached that city at 8 o'clock that night. Judging it of consequences to complete the destruction of the public buildings with the least possible delay, so that the army might retire without loss of time, the following buildings were set fire to and consumed- the capitol, including the Senate house and House of representation, the Arsenal, the Dock-Yard, Treasury, War office, President's Palace, Rope-Walk, and the great bridge across the Potewmac: In the dock-yard a frigate nearly ready to be launched, and a slope of war, were consumed. The two bridges leading to Washington over the eastern branch, had the enemy been destroyed by the enemy who apprehended an attack from that quarter.

The object of the expedition being accomplished, I determined, before any greater enemy force could be assembled, to withdraw the troops, and accordingly commenced retiring on the night of the 25th. On the evening if the 29th we reached Benedict, and re-embarked the following day. In the performance of the operation I have detailed, it is with the utmost satisfaction I observe to your Lordship that cheerfulness in undergoing fatigue, and anxiety for the accomplishment of the object, were conspicuous in all ranks

An attack upon an enemy so strongly posted could not be effected without loss. I have to lament that the wounds received by Col. Thornton, and the others officers and soldiers left at Bladensburg, were such as prevented their removal As many of the wounded as could be brought off were removed, the others being left with medical care and attendants. The arrangements made by Staff Surgeon Baxter for their accommodation have been as satisfactory as circumstances would admit of. The Agent for British prisoners of war very fortunately residing at Bladensburg, I have recommended the wounded officers and men to his particular attention, and trust to his being able to effect their exchange when sufficiently recovered.