HDQRS. DEPT. OF VIRGINIA AND NORTH CAROLINA,
ENGINEER'S OFFICE,
October 10, 1864.

GENERAL: I have the honor to submit the following report of engineering operations in this department for the week ending October 8, 1864,viz:

October 2 a line of defense was determined on by General Barnard and Colonel Comstock, its right resting on Four-Mile Creek and its left on the marsh on the James River below Three-Mile Creek. On the 3d General Butler detailed the One hundred and twenty-seventh Regiment U.S. Colored Troops to report to me for the construction of this line. Selecting Captains Eaton and Dalrymple, of the First New York Volunteer Engineers, I indicated and laid out the details of the whole line with a detached square redoubt on Signal Hill, to the right of the New Market road. At 11 a.m. the same day the parties commenced work, 150 men being occupied on the work at Signal Hill, and from 550 to 600 daily on the line itself, with two companies of the First New York Volunteer Engineers. I have the honor to submit herewith a tracing(*) showing the details of the line. October 8. The work is well advanced. The infantry parapet is nearly two.thirds completed along the line, from 200 yards to the left of the Battery No. 7 to 100 yards to the right of the Kingsland road, near Four-Mile Creek--in all, more than 1,300 yards, exclusive of batteries. The revetment is of rails. Battery No. 1 was commenced today. Battery No. 6 is completed for three guns Battery No. 3 has three embrasures and the interior revetting finished, so that it is now ready for guns. Battery No. 4 is almost finished. The redoubt on Signal Hill has three faces completed, seven embrasures cut, seven platforms raised, and four guns in position. Abatis has been laid on two fronts, as well as on 150 yards of the main line to the rear. At Cox's Hill 40 engineers and 400 infantry have been worked, under the direction of Captain Suess, First New York Volunteer Engineers, since October 5 on a redoubt to command the river above, and act also as a counter-battery to rebel works across the river. The work on the parapet and revetments will be finished by October 9. An outline (+) of the redoubt will be sent with this report. At Dutch Gap engineers have been constructing bomb-proofs for the steam dredge at work there and the steam pump to be used. The excavation will progress rapidly hereafter by means of the dredge, which throws out about 400 cubic feet in twelve hours. The main line of works progresses in strength and protection daily. That portion occupied by the Tenth Army Corps is very weak and not well laid out. It is simply the old rebel line reversed. I have urged a new line, with appropriate works, to protect our right flank and make it secure, but an unwillingness has been manifested to have this carried out for the present. That occupied by the Eighteenth Army Corps, from the left of the Tenth to Cox's Hill, on James River, is secure and in good condition. Fort Harrison has been very much strengthened and closed in rear (our front). Traverses have been erected to protect it from fire in every possible direction. Abatis has been planted around it and the old line destroyed. Redoubts and batteries have been erected along the line from this point to Cox's Hill in the best possible positions to command the ground. Lieut. W. R. King, U.S. Engineers, has been assigned as chief engineer of the Eighteenth Army Corps.

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

                                                                                   PETER S. MICHIE,
                                                                                   First Lieutenant, U S. Engineers,
                                                                                   Acting Chief Engineer,
                                                                                   Dept. of Virginia and North Carolina.
                                                                                       

Brevet Major-general BARNARD,
Chief Engineer, Armies in the Field, City Point, Va.