[March.]-The regiments have not changed their position in the trenches in front of Petersburg.

March 25.- In the morning the enemy attacked that portion of the line occupied by the Third Brigade. As soon as the nature of the move was ascertained two regiments of this brigade (Thirty-seventh Wisconsin and One hundred and ninth New York Volunteers), lying in reserve in rear of Fort Morton, were ordered to take up their line in the right of this brigade, in order to repulse the enemy should they turn the flank of the Third Brigade, but were finally driven back and the line reoccupied.

The troops have been engaged in picket and trench guard duty, repairing picket-line and covered way.

April 1.- In the night a demonstration, was made on the rebel lines, in front of the position occupied by this brigade, in front of Petersburg, Va. The rebels were found in force, and no determined attack was made.

April 2.- Before daybreak the whole brigade, with the exception of the Fifty-first Pennsylvania Veteran Volunteers, which was ordered to hold the line occupied by the brigade, made an assault on the work of the enemy to the right of Fort Sedwick. Their line was carried with great gallantry, five pieces of artillery were captured, also the entire garrison of Fort Mahone-some 400 officers and enlisted men. The lines were held during the day and night.

April 3.- At an early hour in the morning the brigade entered Petersburg, the city being evacuated by the enemy during the night. The loss from the brigade was 25 killed, 150 wounded, and 7 missing.

April 5.- Took up line of march along the South Side Railroad, marching to within two miles of Blacks and Whites Station, arriving there on the 9th instant, where the brigade remained engaged in guarding railroad, doing camp and guard duty, and throwing up inclosed works at the station.

April 20.- In the morning the brigade took up its line of march to City Point, arriving at that place on the morning of the 22nd; embarked immediately on transport for Washington.

April 24.- In the morning arrived at Alexandria, Va. The brigade went into camp about three miles from the city.

April 26.- In the morning the brigade took up the line of march for Washington, arriving at 4 p. m., and encamping at Tennallytown, about four miles from the city, where the troops still [April 30] remain.

Second Brigade, First Division.

[March.]- The command has remained in camp at its old position, in front of Petersburg, Va., near the Appomattox.

March 25.- The line of the Third Brigade of this division was carried by the enemy, and the works known as Battery Numbers 10 and Fort Stedman captured. They also assaulted Battery Numbers 9 (garrisoned by troops of this brigade), but were severely repulsed after a brisk battle of about three hours. The enemy withdrew in haste to his own line of works, having been severely punished for his temerity. In the engagement the brigade captured 16 rebel commissioned officers and 316 men, rank and file. The action commenced at about 4 a. m.

March 29.- Late at night there was brisk artillery and musketry firing on the line, which continued tail nearly morning of the 30th. There was do advance made by either party, however, and the only result was a few casualties.