Our signal corps intercepted to-day some fifteen of the enemy's signal messages, many of which are lengthy and all unimportant; hence they are not entered.

October 12, 1863.-There is no charge in the fleet off the harbor this morning.

The enemy are throwing up another line of works from southwest side of Gregg to the marsh. An embrasure cut in Gregg bearing on Fort Johnson is masked by filling it up with sand bags. Two mortars thought to be in position in their new mortar battery on the east side of Gregg. No guns are visible in the battery just constructed between Gregg and Wagner. The Parrott gun at Battery No. 1, Morris Island, has been removed.

As usual, Moultrie, Simkins, and Cheves continued firing on the enemy to-day, but did not elicit any reply until the afternoon, when a few mortar shells were fired from the battery in the vicinity of Gadberry Hill against Simkins and Johnson. No casualties or damage.

October 13, 1863.-The Federal fleet inside the bar and off the harbor remains unchanged, with the exception of one additional schooner.

The operations of the enemy apparent activity displayed by them to-day than usual.

Thirty-nine shots fired by Simkins and 38 by Cheves; effect not reported. At the former battery an "infernal machine" floated up last night and was secured. [No description of it is given in the report.]

A platform for Mortar No. 2 at Battery Haskell is being laid down by the engineer corps, and the bomb-proof at that work is under construction.

[One private of Company E. Second South Carolina Artillery, severely wounded at Fort Johnson.*]

Dispatches from the Stono state that 87 men with knapsacks crossed Stevens' Bridge and proceeded toward Dixon's Island. The enemy's pickets are still on Horse and Horseshoe Islands.

Brigadier-General Mercer, commanding at Savannah, in reply to telegram from these headquarters, telegraphs that 200 of the Fifty-seventh Georgia Regiment have arrived in Savannah. He also acknowledges receipt of order directing [Robert H.] Anderson's regiment to prepare to march at a moment's notice.

October 14, 1863.-Raining this morning, and atmosphere too hazy to see number and character of the enemy's fleet. One or two vessels arrived from the northward, loaded, but did not bring any troops. Fort Moultrie, Simkins, and Cheves fired slowly on the enemy during the day, but elicited no reply. Only 29 shots fired from Simkins and 3 from Cheves.

About 60 hands are engaged on the bomb-proof at Haskell, and 10 hands on the mortar platform at the same battery.

Reports from the Stono are unimportant.

The following are copies of some of the signal messages sent by the enemy and intercepted by our signal corps:

General T-:

How is the mounting of guns in Wagner progressing? Hurry the completion of small scows Captain B- is building.

G-,

General.

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*So reported by Colonel George P. Harrison, jr.

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