To show the character of the bridges last referred to I will state that on Saturday last, May 24, seventy-nine regiments, more than 900 wagons, and several batteries of artillery passed over these two bridges at Bottom's Bridge Crossing between sunrise and sunset, as reported to me by First Lieutenant Hine, of Company E, in charge of guard at that crossing.

A fourth detachment, under Major Embick, was assigned as follows:

I commenced work on the railroad bridge near Tunstall's Station on Monday, May 19, and on Saturday, the 24th, about 5.30 p. m., first locomotive passed over. The bracing and filling up around mud-sills was completed on the 26th. This bridge consists of one span 50 feet, 21 feet high of trestle work, and would have been completed much sooner but for the lack of facilities for getting timber from the woods to the bridge, the scarcity and very indifferent assortment of tools, and some bad weather. The detachment also repaired a portion of the track, which work was finished on Tuesday, May 27.

A fifth detachment, under Colonel Stuart, was also assigned to the same duty. He reports as follows:

On Friday morning, May 23, I reached the railroad bridge over the Chickahominy with detachments from Companies I and K, where I found three spans of trestle work, each 11 feet wide and 15 feet high, and one truss span of 44 feet, same height, entirely destroyed by fire; two other trestle spans were partially destroyed. Found a hand car and a quaintly of timber at a saw-mill 3 miles east of bridge, near the track, which were brought up and work commenced.

On Sunday, the 25th, Captain O'Grady and First Lieutenant Andrus, of this regiment, made a thorough examination of the bridge west of the portion destroyed, about 1,000 feet in length, and also of the track for 4 miles west to Fair Oak Station, and reported the bridge-work in safe condition for passing over.

On Monday morning the trestle spans were repaired and work commenced on truss span, when Engineer Charles McAlpine arrived with 40 bridge carpenters of the Government bridge-builders and a car load of sawed timber and a full supply of necessary tools. With their valuable aid the bridge was completed on Tuesday, May 27, at 7 p. m. when a locomotive passed over the bridge and went 3 miles beyond. I have left 10 men as a guard at the bridge until relieved, and respectfully recommend that a larger guard be sent there from some other regiment, as the bridge is long and high and requires a much larger guard.

RECAPITULATION.

Bridges built and repaired.-One bridge, single span, 26 feet, at Black Creek; one bridge, two spans, 18 and 20 feet, respectively, roadway 12 feet, at Mill Creek; four small bridges on the turnpike between Black Creek and a point half a mile beyond the blacksmith's shop; three bridges between the last point mentioned and half a mile beyond the White Curch, over streams 8 feet in width and 5 in depth, built with stringers laid on crib abutments; two trestle bridges, 120 feet in length, across the Chickahominy at Bottom's Bridge; timber got out and framed for a bridge across the Chickahominy at New Bridge, 114 feet in length, seven spans; two trestle bridges ready to be thrown at the same spot.

Railroad bridges.-One bridge, one span, 50 feet in length, 21 feet in height, trestle work, near Tunstall's Station; one bridge, three spans, trestle work, each 11 feet in width, 15 feet in height; one truss span, 44 feet in width, 21 feet in height; two trestle spans repaired over the Chickahominy; assisted by forty Government bridge-builders.

Roads repaired.-One hundred any fifty feet graded and corduroyed on the turnpike from White House at railroad crossing; 1,000 feet ditched, graded, and corduroyed between Black Creek and a point half a mile beyond the blacksmith's shop; 800 feet ditched, graded, and corduroyed near White Curch; 4,000 feet road, 50 feet in width, cut through the woods near the Chickahominy; 1,000 feet corduroyed I