which the enemy seems to aim necessary, and he therfore wishes you to send off at once one of your brigades to Johnson's Crook. This brigade will leave a regiment at Nickajack Trace, and you are to consider it most important that all the trails and gaps of the mountain are to be watched and guarded. The commander of the troops sent will be so instructed. Colonel Grigsby, commanding the cavalry near Trenton, has been ordered, in case he is driven back, to occupy the passes in the mountain and to hold them. Please communicate with him, and let him know that you will co-operate with him. In addition to the above disposition, the commanding general desires that you will have the balance of your division, except Law's brigade, in readiness to move in the same direction at daylight to-morrow.

I am, general, very respectfully, your obedient servant,

G. M. SORREL,

Assistant Adjutant-General.

[31.]

HEADQUARTERS LONGSTREET'S CORPS,
October 27, 1863.

Colonel J. WARREN GRIGSBY,

Commanding Cavalry, near Trenton:

It is reported, though not confirmed, that a force of the enemy is advancing from the direction of Bridgeport upon Trenton. The lieutenant-general commanding desires that you will ascertain the truth of this report. If you find yourself compelled to fall back from Trenton, he wishes you to do so by the valley, holding the trails or gaps in the mountain behind you. To do this your men must be dismounted, and should know that the gaps are to be held. Please communicate your movements and let us know whenever you may be forced back to the gaps. Please understand what position you are to hold. The enemy must not be allowed to possess Lookout Mountain, and to prevent this you must hold the trails or gaps on the west side of the mountains until assistance can reach you. Let us know promptly the moment you may be forced to these positions.

Very respectfully, your obedient servant,

G. M. SORREL,

Assistant Adjutant-General.

[31.]

HEADQUARTERS LONGSTREET'S CORPS,
October 27, 1863-10 p. m.

Colonel J. WARREN GRIGSBY,

Commanding Cavalry:

I am in receipt of yours of 3.30 p. m. I wrote you this afternoon, by direction of the commanding general, in reference to holding the passes of the mountains in the event of your being driven from your present position and pressed by an overwhelming force of the enemy. I desire now to repeat those instructions. The enemy must not be permitted to gain possession of Lookout Mountain, and if you are forced back, the passes leading to its possession must be held by your men dismounted until infanry can reach you. General Jenkins will co-operate with you, if necessary, and we should have early advices of your movements.

I am, colonel, very respectfully, your obedient servant,

G. M. SORREL,

Assistant Adjutant-General.

[31.]