REMARKS OF D. B. HARRIS.

OFFICE CHIEF ENGINEER OF DEPARTMENT, Charleston, January 14, 1864.

General G. T. BEAUREGARD,

Commanding Dept. S. C., Ga., and Fla., Charleston, S. C.:

GENERAL: I have the honor to reply to the accompanying queries, addressed to Brigadier General R. S. Ripley, commanding First Military District, by Lieutenant Colonel A. Roman, assistant inspector-general, under date of December 12, 1863, which have been referred to me form my remarks.

1. Morris Island offers much greater natural advantages than Sullivan's Island against such a combined attack by land and sea as was made on the 10th of July last-the natural formation of the sand-hills on the sound end of Morris Island being much better calculated, without the aid of artificial defenses, to repel na attack across Highs-House Inlet than those of Sullivan's Island across Breach Inlet. The sand-hills on the south of Morris Island also offer much better cover for troops than the corresponding hills on the east of Sullivan's Island.

2. Two thousand infantry, in addition to the artillery requisite ot serve the guns on Morris Island, could have repulsed the attack of the enemy on the 10th of July. Three thousand men of all arms I should have regarded as a full garrison for the island. Sullivan's Island,not having been threatened with a land attack at that time, 1,500 infantry, in addition to the cavalry and artillery on the island, would have been, I think, sufficient for the safety of the island. Thirty-five hundred men of al arms would have then constituted a full garrison for that island.

5. The only labor available for the works on the south end of Morris Island was details of soldiers from Colonel Graham's regiment-say of 100 to 150 men daily-which Captain Cheves reported were so steadily employed as "to prejudice their drill and other camp duties."

6. It would have taken twelve months to have constructed such a work at Battery Marshall now is, on the south end of Morris Island with this force.

7. Orders were given for the erection of the detached batteries on the 10th of March, and the work was commence two days thereafter.

8. The works that I contemplated constructing would, if finished, have permitted a reduction of 300 to 500 men in the forces necessary to have repelled the assault of the 10th of July.

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

D. B. HARRIS,

Colonel, and Chief Engineer of Department.

[Indorsement.]

HDQRS. DEPT. SOUTH CAROLINA, GEORGIA, AND FLORIDA, Charleston, s. C., January 16, 1864.

I fully concur in the opinion expressed by Colonel Harris in this communication, in answer to the questions referred to.

G. T. BEAUREGARD,
General, Commanding.