NEW MADRID, MO., March 5, 1862.

General LEONIDAS POLK, Commanding:

GENERAL: Colonel Richmond left here last evening. At 12 o'clock last night the enemy drove in our pickets at the upper fort at this place. The guards at the lower fort repulsed them easily. This guard was from Colonel Scott's regiment. Artillery was then opened upon us. Our gunboats returned the fire and soon drove them back. No attack was made by infantry upon our works.

If 30,000 or 40,000 men could be thrown promptly to Point Pleasant the force in my front could be defeated and captured. I throw out this suggestion. I admit that if their gunboats should pass Island Numbers 10 and defeat Commodore Hollis, that force would be cut off from Tennessee. If such an enterprise was undertaken the transports carrying the troops should rendezvous at Tiptonville. The sooner undertaken the easier performed.

I send this by Captain Lewis.

Yours, &c.,

J. P. McCOWN,

Brigadier-General.

N. B.-The Federal troops were cheering for General McClernand last night.

Two Federals were wounded and are prisoners. Number of articles were taken, blankets, &c.

MADRID BEND, March 5, 1862-9 p. m.

Major General LEONIDAS POLK:

GENERAL: I am just from New Madrid. The pickets have been fighting all day. The enemy was in line, only out of range of our guns. One piece (6-pounder) was advanced to within 400 yards of our pickets. I directed the pickets not to notice it. I shall risk nothing in the open field with my small force.

Guns are being rapidly mounted at this place. Gun-carriages, ammunition, &c., came here in such confusion that it is difficult to find anything.

I fear the Battery Numbers 1 will be next to useless.

Guns of all kinds, forty-seven guns. All I fear is that the Federal gunboats may close their post and run past. We have not a single magazine here.

I received your telegram of 3rd instant. New Madrid must be in our possession. To hold this without New Madrid would require a much larger force than I have.

If New Madrid is in our possession and we can keep back the gunboats, a force could be landed near Point Pleasant and the force in my front captured.

I have not yet beet able to turn my attention to Tiptonville. The island opposite that place is under water.

It is useless to deny that my condition is critical in the extreme. I shall do all in my power. My command is in fine spirits.

Yours, &c.,

J. P. McCOWN,

Brigadier-General, Commanding.