Creek, a branch of the Stono, below Church Flats. This river must be examined from the latter point to the Wappoo Cut to determine if there are any landing places by which the works at the overflow could be turned. There are two inclosed field works --- miles from Charleston, commanding the road from Savannah to the long or new bridge across the Ashley. They appear to be well located, provided they cannot be turned on the right or left toward the Wappoo, which must be inquired into if they are unarmed.

September 21.-I inspected this day the defenses of Savannah with the same officers and General Mercer, commanding. They are not yet completed, but are progressing rapidly. Those on the river, I am informed, are finished, Fort Boggs expected, which has, however, its armament, sixteen guns, in position. The line of lunettes and redans around the city are about half finished, I should judge. These works are rather too close to each other and unnecessarily strong in profile. There are about 1,400 men (negroes) at work upon them. The obstructions, piling and crib work, filled in with stones and bricks, about 1 mile below Fort Jackson and its batteries, are nearly completed, requiring about ten or fifteen days longer to finish them. They will then obstruct very thoroughly, I think, the navigation of the river. They will, however, require to be watched and repaired constantly, owing to the effect of the current on the bottom between the cribs.

The outer line of defenses, consisting of detached works or batteries at Thunderbolt and other points, armed with heavy guns, were not visited for want of time, but I am informed by General Pemberton that they are completed, well armed, and with a proper garrison could not be taken by the enemy if well defended. By their advantageous position they cannot be turned. He places great reliance on them. An additional work of Coffee Bluff, on the Ogeechee, ought to be constructed, in the opinion of the chief of engineers of the Georgia District, Captain McCrady. This must be looked into.

Upon the whole I consider Savannah thoroughly defended from a naval attack, and when its line of land defenses will be completed, with a proper garrison of about 15,000 men, may be considered impregnable until the enemy shall bring against it an overwhelming force, which it is not probable they will ever attempt, as the result, if favorable, will not compensate them for the expense and trouble.

September 24.-I inspected this day with Colonel Gonzales the line of works on the Neck to defend the city of Charleston from land attack from the north. It is a continuous bastion line of strong profile and elaborately constructed, but badly located, I believe, not being well adapted to the ground. It is commanded to a certain extent by woods in front, and can be enfiladed and taken in reverse by gunboats on the Cooper and Ashley Rivers, particularly from the last. No traverses have been constructed. They are absolutely required. Even then this line could hardly be held successfully against a fleet of gunboats in each of said rivers. The two batteries at the Half-Moon Battery are not finished. They are intended for five and three guns each, to command the Cooper River and Town Creek. The distance to the former is too great. A much better position could be found, I think, on the opposite side of the river at Hobcaw Bluffs, but obstructions would also be required. The profile of the parapet of those batteries is too great, especially of the first one. Adaptation of "means to an end" has not always been consulted in the works around this city and Savannah. Much unnecessary work has been bestowed upon many of them.

G. T. BEAUREGARD,

General, Commanding.