Affairs in Louisiana.
Pascagoula, Jan. 25.
--A gentleman who left the neighborhood of Covington, La, on the 18th inst., says that on the 7th two of the enemy's gunboats and six transports appeared off the mouth of the river and commenced shelling the marsh, when a Confederate picket of seven men, under the charge of a Sergeant, started from Madisonville in a skiff on a tour of observation, and are supposed to have been captured, the Sergeant being the only one known to have escaped.
The fleet then proceeded up the river and took possession of the latter place and four saw-mills which our forces neglected to destroy.
They threw out pickets on the Covington road within two mites of that town, and also on the Madisonville road, on the east side of the river.
Our informant was at Covington on the 7th, and started for Madisonville the same night, in company with two others, being ignorant of the near approach of the enemy.
The other two were captured, but our informant, though repeatedly fired at, escaped unhurt.
He estimates the enemy's force at not more than two or three hundred.
They are engaged in raising the hulls of several vessels sunk in the river by our authorities.
Our force at Covington at the time consisted of one company — Greenlee's Sharpshooters — which withdrew towards Franklinton.
He represents the trade in cotton carried on between Amite Summit and other places on the New Orleans and Jackson Railroad and Baton Rouge as very extensive, and without molestation.
Four gunboats were in sight yesterday--three off Round Island.
Others have proceeded towards Ship Island. 