General Birney commanding, and Mackenzie's cavalry, took up his line of march in pursuance of the foregoing instructions, and reached the position assigned him near Hatcher's Run on the morning of the 29th. On the the following instructions were given to General Sheridan:

CITY POINT, VA., March 28, 1865.

Major General P. H. SHERIDAN:

GENERAL: The Fifth Army Corps will move by the Vaughn road at 3 a. m. to-morrow morning. The Second moves at about 9 a. m., having but about 3 miles to march to reach to point designated for it to take on the right of the Fifth Corps, after the latter reaching Dinwiddie Court-House. Move your cavalry at as early an hour as you can, and without being confined to any particular road or roads. You may go by the nearest roads in rear of the Fifth Corps, pass by its left, and passing near to or through Dinwiddie, reach the right and rear of the enemy as soon as you can. It is not the intention to attack the enemy in his intrenched position, but to force him out if possible. Should me come out and attack us, or get himself where he can be attacked, move in with you entire force in your own way, and with the full reliance that the army will engage or follow, as circumstances will dictate. I shall be on the field, and will probably be able to communicate with you. Should I not do so, and you find that the enemy keeps within his main intrenched line. you may cut loose and push for the Danville road. If you find it practicable, I would like you to cross the South Side road, between Petersburg and Burkeville, and destroy it to some extent. I would not advise much detention, however, until you reach the Danville road, which I would like you to strike as near to the Appomattox as possible. Make your destruction on that road as complete as possible. You can then pass on to the South Side road, west of Burkevile, and destroy that in like manner.

After having accomplished the destruction of the two railroads, which are now the only avenues of supply to Lee's army you may return to this army, selecting your road further south, or you may go on into North Carolina, and join General Sherman. Should you select the latter course, get the information to me as early as possible so that I may send orders to meet you at Goldsborough.

U. S. GRANT,

Lieutenant-General.

On the morning of the 29th, the movement commenced. At night the cavalry was at Dionwiddie Court-House, and the left of our infantry line extended to the Quaker, road, near its intersection with the Boydton plank road. The position of the troops, from left to right, wa as follows: Sheridan, Warren, Humphreys, Ord, Wright, Parke. Everything looked favorable to the defeat of the enemy and the capture of Petersburg and Richmond, if the proper effort was made. I therefore addressed the following communication to General Sheridan, having previously informed him verbally not to cut loose for the raid contemplated in his orders until he received notice from me to do so:

GRAVELLY CREEK, March 29, 1865.

Major General P. H. SHERIDAN:

GENERAL: Our line is now unbroken from the Appomattox to Dinwiddie. We are all ready, however, to give up all, from the Jerusalem plank road to Hatcher's run, whenever the forces can be used advantageously. After getting into line south of Hatcher's we pushed forward to find the enemy's possible. General Griffin was attacked near where the Quaker road intersects the Boydton road, but repulsed it easily, capturing about 100 men. Humphreys reached Dabney's Mills, and was pushing on when last heard from.

I now feel like ending the matter, if it is possible to do so, before going back. I do not want you, therefore to cut loose and go after the enemy's roads at present. In the morning push around the enemy, if you can and get on to his right rear . The movements of the enemy's cavalry may, of course modify your action. We will act all together as one army here until it is seen what can be done with the enemy. The signal officer at Cobb's Hill reported, at 11.30 a. m., that a cavalry column had passed that point from Richmond toward Petersburg, taking forty minutes to pass.

U. S. GRANT,

Lieutenant-General.