Third Brigade, First Division, U. S. Colored Troops.

June 11.- The brigade left Mobile, Ala., by steamer for New Orleans, La., at which place it arrived on the 12th; moved to and encamped at Greenville, La., same day.

June 25.- Left Greenville by transports for Alexandria, La., where it arrived on the 28th; encamped opposite the city at Pineville, La., where it still [June 30'] remains.

Separate Cavalry Brigade.

March 4 to 19.- Was occupied in transporting this brigade from Carrollton to Barrancas, where, in obedience to orders from headquarters Military Division of West Mississippi, the Separate Cavalry Brigade was constituted a part of Major-General Steele's command.

March 20.- Received marching orders and proceeded to Pensacola, from whence moved on the following day in advance of the army in the direction of Pollard, Ala. Our progress for the first week through the country was slow, in consequence of the almost impassable condition of the roads.

March 25.- We met and defeated a brigade of Alabama mounted troops, under command of Brigadier-General Clanton. The result of our victory was the capture of 118 prisoners, officers and men, including Brigadier-General Clanton, who was severely wounded, 1 battle-flag, horses, arms, &c., and the complete disorganization of the brigade opposed to us. Our loss was 1 officer and 2 men killed, and 1 officer and 2 men severely wounded, all from First Louisiana Cavalry. Reached the Escambia River the same day. The day following destroyed part of the bridge of the Mobile and Great Northern Railroad over the Escambia River, and a portion of the railroad track. Reached Pollard the same day.

March 27.- Left the Escambia, and taking up our line of march westward, reached Weatherford's plantation, four miles from head of Perdido River, March 31. Our animals are suffering for want of forage.

April 1.- Arrived at Blakely; found a force of rebel infantry outside the place, which my advance charged, capturing 75 prisoners and 1 battle-flag. Drove the enemy inside his works, where he opened fire with artillery. Encamped for the night two miles from the place.

April 2.- Assisted in the investment of Blakely, holding position on extreme right and left. Withdrew my troops and encamped between Spanish Fort and Blakely. Lost several horses and men by torpedoes in the road. Remained in this position until the 9th, scouting and guarding communications in the rear, when, in accordance with orders, moved in the direction of Claiborne.

April 11.- When ten miles from Claiborne met the Fifteenth Confederate Cavalry (regulars;) threw the First Louisiana Cavalry into line of battle, charged them after a short fight, broke their line, and completely dispersed them. Captured 2 officers, 70 men, 2 battle-flags, arms, &c. Our loss was slight. Occupied Claiborne same night. Remained there until the 15th instant, when we marched in the direction of Blakely. Reaching Stockton, received orders to march to Greenville. Received supplies at Stockton and marched same day in compliance with orders.

April 25.- Reached Greenville; received orders to proceed to Eufaula. Sent our train from Greenville to Montgomery.

April 27.- Marched toward Eufaula.