Third Ohio Volunteer Infantry; T. B. Stevenson, first lieutenant. They state that there are 650 U. S.officers now confined in the jail at Charleston, lately brought there from Macon, Ga. Two other parties of prisoners, amounting to about 1,000, were started for Charleston, but were, for some reason, not sent through. My fire on the city will continue as before until I receive orders to the contrary. These officers report that communication between Charleston and Atlanta has been interrupted since the 29th ultimo. They also state that a party of 60 U. S. officers effected their escape somewhere near Charleston, and will try to get through to our lines. I shall do everything possible on my front to meet and assist them, sending out parties on Kiawah, Seabrook, and John's Islands. Further particulars of information may be furnished by the gentlemen themselves, whom I herewith forward. Inclosed please find a copy of a report from the commanding officer of the boat infantry of a late reconnaissance around Sumter.

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

A. SCHIMMELFENNIG,

Brigadier-General, Commanding District.

Captain W. L. M. BURGER,

Assistant Adjutant-General.

HDQRS. NORTHERN DISTRICT, DEPT. OF THE SOUTH, Morris Island, S. C., August 16, 1864.

CAPTAIN: I have the honor to report as follows:

Since my last report, August 3, the enemy has shown no changes of any importance on my front. From the outpost reports it appears that his force is larger than before our last demonstration on his lines. This agrees with the accounts given by deserters. They state that of the re-enforcements sent from Atlanta to General Jones at the beginning of last month,the Fifth and Forty-seventh Georgia Infantry have been kept on John's and James Islands ever since. Consequently our late operations in this region did more than temporarily reduce the force at Atlanta. I have no information direct from the enemy's lines within the last eight days, but the fact that the number of the Union prisoners in Charleston has been increased rather indicates that the enemy intends to make Charleston something of a base, and consequently will not reduce his force there.

I have the honor to annex a report giving the regiments, their strength, and locality in the enemy's position. It sums up as follows: Old troops, from 6,000 to 7,000 men; able-bodied civilians in the employ of the Government, 1,000 men; State reserves, 1,000 men; negro workmen, 3,000 to 4,000 men. The same disproportion exists between my artillery force and the enemy's. Against my one light battery he has five at his command; against my 100 heavy guns he has 200 in position. The large supply of workmen above mentioned has enabled the enemy to commence digging again all along his lines. He is erecting new batteries north of Battery Beauregard; another makes its appearance to the east of and close to Battery Bee; Sumter he is repairing constantly under our fire; large fatigue parties were seen for three days at work on Castle Pinckney as in mounting some heavy guns, perhaps the 600-pounder Blakely