The Tenth Main Battalion was organized on the 26th day of April, 1863, from the three years men of the 10th Me. Regiment.

Of the companies of this regiment, two, A and D., were originally mustered into the U. S. service for the term of three years, and all recruits received by the regiment after its departure from Maine were enlisted and mustered for the same period.

On the 25th day of April, the aggregate of Co. A was 55, and of Co. D, 54 men. The rolls of the other eight companies bore the names of 137 men who were mustered for three years.

On Sunday, Apr. 26th, 1863, the following order was received at the regiment from Corps headquarters:

Special order No. 100.

[Extract.]

The enlisted men of the Tenth Maine Volunteers, whose term of service extends to three years or during the war, will be marched to the these head quarters in charge of the following named officers: Captain J. D. Beardsley, Lieut. Charles F. King, Lieut. Chandler Libbey, Lieut. Charles H. Haskrll, and Asst. Surgeon H. N. Howard.

These men will be constituted a provost guard, relieving the three companies of the second Massachusetts Volunteers now on duty at these head quarters. They will be allowed to retain their full proportion of camp and garrison equipage.

By command of Major General Slowcum.

(Signed) H. C. ROGERS, Assistant Adjutant General."

In obedience to this order, the officers and men referred to reported at corps head quarters the same day, and by direction of the Major General commanding were at once organized into a battalion of three equal companies. Companies A and D preserved their original organizations. To company A were transferred the three years men from Company K., and a part of those from H. To D were added the men from F and C. The men from B, E, G, I, and the remainder of those from H., were formed into a new company (B), to the command of which Lieut. C. H. Haskell, formerly of Company F, was assigned.

On the 27th of April, 1863, the Battalion, with the rest of the 12th Corps, proceeded to the Rappahannock River, which they crossed on the 29th, and arrived at Chancellorsville on the 30th.

On the 2d and 3d of May, although not actively engaged with the enemy, they were exposed to their fire, and lost 2 men killed and 2 taken prisoners.

On the evening of May 5th, they re-crossed the Rappahannock River, and on the 6th re-occupied their old camping ground at Stafford Court House, where they remained until the 13th of June, when they moved by way of Fairfax and Edward's Ferry into Maryland and ultimately into Pennsylvania, participating in every part of the campaign resulting in the battle of Gettysburg.

From the 1st of Aug. until the 24th of Sept., they were encamped along the Rappahannock and Rapidan Rivers. On the latter day they proceeded with the 12th Corps to Brandy Station, Va., and there embarked for Tennessee.

After a tedious journey of eight days and nights by rail, they reached Nashville, where they remained three days, and then proceeded to Wartrace. They remained encamped at that place until the 1st of Nov., 1863, when they were assigned to the 29th Regiment Infantry, then organizing, and which they joined at New Orleans, La.