Since writing the above, Major-General Grant directs me to say that he has received instructions (copies of which will be sent you) to re-enforce Major-General Rosecrans, and that he has telegraphed Major-General Halleck the number of troops he will send to Major-General Rosecrans, and, until further orders are received from Washington, it will be impossible to give you the division promised in the accompanying communication. I would account for my silence by saying that the boat bearing this dispatch is the first which has left this place since my arrival. Major-General Grant will keep you informed of all changes which take place during my absence up the river.

I have the honor to be, general, very respectfully, your most obedient servant,

R. T. DUNHAM,

Captain, and Assistant Adjutant-General.

HDQRS. SECOND DIVISION, THIRTEENTH ARMY CORPS,
Morganza, La., September 22, 1863.

Brigadier General CHARLES P. STONE,

Chief of Staff, New Orleans:

GENERAL: General Vandever has jut returned from a thorough reconnaissance of the enemy's position, and brings in with him some prisoners. From one of them, I learn that great alarm existed in Green's camp on the 20th, caused by a report that our troops were approaching by way of Opelousas. One brigade was ordered to march, and did go half-way to that place, but was ordered back by General Taylor. Green has been re-enforced by a brigade of infantry and a battery. He has now two brigades of cavalry, one of infantry, and eighteen pieces of artillery (three four-gun batteries and one six).

These brigades average 1,500 men each. All detachments through the country have been ordered in. There is one brigade of infantry at Vermillionville and a small force at Washington, guarding ammunition and supplies. Kirby Smith has just arrived at Alexandria from Shreveport, and Taylor is at Washington. The movement from below has disconcerted them. The prisoners think, if it had not been made, they would have concentrated, crossed at Simsport and Morgan's Ferry, and attacked me.

I send below to-day for cavalry ammunition and a change of clothing for the men; also sending down the sick, and ordering up the convalescents from camp. In the meantime will make some arrangements for a crossing, and be ready for any movement. They are evidently afraid to go away, leaving my force in their rear; will keep a close watch on every movement.

Very respectfully, your obedient servant,

F. J. HERON,

Major-General.

HEADQUARTERS DEPARTMENT OF THE GULF,
New Orleans, September 22, 1863-6.30 a. m.

Major-General FRANKLIN, Berwick City:

SIR: The tug Leviathan was captured by the rebels at 4 a. m. to-day at Southwest Pass. Look out for your boats in the bay and river.

Very respectfully, your obedient servant,

[CHAS. P. STONE,]

Brigadier-General, and Chief of Staff.