former position is Major with his division; at the latter Bagby with his, lately Bee's, who has been relieved from duty with this army. The enemy were driven to within 3 miles of Alexandria along the river, Hardeman's advance squadron charging 600 Yankee cavalry, driving them in and taking prisoners. Roads are being cut to connect Major and Bagby by short lines so as to concentrate rapidly on either position. Four of the guns from the Signal are ready for action with a good supply of captured ammunition. The blockade of the river has continued for ten days complete, every boat, whether gun-boat or transport, having been taken or destroyed that attempted the passage. For four days no attempt has been made. This morning at dawn I attacked the enemy at the lower Chambers place, on the Bayou Robert, with Steele's division of cavalry, supported by Polignac's infantry. Steele drove the enemy rapidly to Governor Moore's upper place, capturing cooking utensils, tents, and horses, and followed hard until he found their infantry displayed in line. To-night, about an hour before dear, I will renew the attack, using Steele, Polignac, and artillery, and try and drive him beyond John Williams'. This will connect Steele's pickets on the Bayou Robert with Major's on the river road and prevent the enemy from camping on the high ground of Bayou Robert. In case we find too much strength we can easily draw off at so late an hour without risk of being followed. On the Rapides road I have but one regiment of cavalry and a section [of artillery]. Pickets connect through the swamp with Bayou Robert. All cattle, &c., have been removed from the Rapides country for 18 miles, so the enemy has no object in pushing in that direction even if he dared to do so; the whole country to the Gulf and Sabine being open to me, I have no line of supplies or base of operations, and can move where I pleas. On the north side of Red River everything is watched from above Pineville to opposite Major's batteries, where communication is established. All the roads from Pineville to the Ouachita and Black Rivers have been ordered to be blocked by felling trees across them and destroying the bridges on the Flaxon and other streams. thus we have a continuous line of pickets inclosing Banks' army and Porter's fleet, and they are as closely besieged as was ever Vicksburg. Every day the enemy is attacked and driven on some road and kept continually harassed by feints, driving in pickets, &c. Thus he is expecting an assault every moment, and is uncertain of the direction whence it may come.

To keep this up, with my little force of scarce 6,000 men, I am compelled to "eke out the lion's skin with the forx's hide." On several occasions we have forced the enemy from strong position by sending drummers to beat calls, lighting camp-fires, blowing bugles, and rolling empty wagons over fence rails. If we force the enemy from Bayou Robert to-night I will move Polignac at once to Marksville. From Marksville he can support Major or Bagby, throw himself with them upon any force attempting to reach alexandria from Simsport, and will be 20 miles nearer Trinity than Banks at Alexandria. Should Banks retreat by Trinity on Natchez, the cavalry will cross from their present position and strike in on his line through the pine woods. Polignac, with all the artillery, will move rapidly to the mouth of Red River and salute whatever portion of the invading army may seek to reach New Orleans by the Mississippi River. Arrangements for crossing both the Red and Atchafalaya Rivers have been made.