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

GENERAL: I have the honor to submit the following as my report of engineering operations in this department for the week ending October 1, 1864, viz:

A tracing of a rebel map found on the body of General Chambliss was made from the original, which was lent to this office by Major Michler, chief engineer, Army of the Potomac, and seventeen copies (photographic) were made and distributed by direction of the major-general commanding this department.

Early in the week General Butler informed me of contemplated movements north of the James River, so that pontoon bridges should be ready at the proper time. The bridges at Deep Bottom, on the James River, and at Broadway, Appomattox River, were covered with manure on the 26th to deaden the sound of travel over them. On the 27th a survey was made of the banks of the James River in the vicinity of Aiken's Landing, to determine the site for a new bridge to be used in the coming movement. An excellent location was found about 600 yards below Aiken's house, there being good approaches on both sides. Generally, along the James River, while one side is good the opposite is marshy, and it is rarely that two points directly opposite can be found that will admit to be used for the abutments of a bridge unless first a long corduroy road is built on one side. The width of the river at the point designated is 1,320 feet, requiring sixty-seven boats for the construction of the bridge, including the two additional ones for the draw. The details of construction were intrusted to Capt. James W. Lyon, chief pontonier, Army of the James, who has proved himself in every case a most reliable and skillful 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.