ful officer. Thirty-six boats were brought by water from Broadway Landing and thirty-nine from Deep Bottom. One lieutenant and fifty men were each detailed from the company of pontoniers attached to the Army of the James, and from the command of Captain Lubey, Fifteenth New York Volunteer Engineers, at Deep Bottom, and these constituted the whole party engaged on the bridge. The success of the entire movement depending upon its secrecy quiet and good order was strictly enforced. The work was commenced at 7.30 p. m. and finished at 2 a. m. 29th of September. At this time it was dead low water, and the last nine boats had to be dragged over the soft mud and placed in position by hand. Had the tide been favorable the bridge would have been finished at 11 p. m. The infantry began coming at 3 a. m., one hour after its completion, and not till then did the enemy's pickets have any idea of its existence. On the 29th the advance was made and at noon our troops were in possession of a part of the defenses at Chaffin's farm. Toward noon the troops occupied the line indicated by General Barnard and Colonel Comstock, who were present during the day. On the 30th engineer troops and infantry were engaged in strengthening the line, changing the front of Fort Harrison (captured), laying abatis, and otherwise making the position strong. On the 1st October I was sent with General Terry, who made a demonstration on the Darby road toward Richmond, approaching with his advance to within 500 yards of the second line of works to the right of this road. The topography and other details of the rebel map heretofore referred to were found to be very accurate, except in one or two minor details, such as names of a few of the houses being changed, &c. The heavy rain and murky atmosphere prevented a close and satisfactory inspection of their works, but I feel convinced that their general character is the same as laid down in the map. We met no infantry outside of the works, and but very few of their cavalry.

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.

[Inclosure Numbers 3.]

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

October 10, 2864.

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

On 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 3rd 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