DECEMBER 6, 1862.

Major-General BURNSIDE:

General Ingalls telegraphs this morning in regard to railroad iron, and says it is your wish to have some afloat, to be taken up the Rappahannock. Is this the best practical arrangement? If rails are taken by water to Fredericksburg, they cannot be loaded and transported on the railroad without cars and engines, and cars and engines cannot be procured until the bridge is finished. If we wait for the bridge, we can send the iron ready loaded to where we may wish to use it without a transshipment at Fredericksburg, which would be very troublesome. If the idea is to haul by wagons from Fredericksburg, in case the track is torn up near that place, it will be almost as convenient to haul from Falmouth over the wagon bridge, which must necessarily be built, in the event of our getting possession of the city. In any event, I do not perceive that the sending of rails by water to Fredericksburg is necessary; but it shall be done if you desire it. My latest information was that the rebels were still running trains to Fredericksburg. If so, the track is not yet torn up, and if you turn their position the retreat of the enemy will probably be too precipitate to permit them to do much damage. Although we have probably iron enough, I will order 10 miles more immediately, to make sure. Please show this telegram to General Ingalls, to avoid the necessity of repeating it to him.

H. HAUPT.

(Copy to General Halleck.)

HDQRS. ONE HUNDRED AND TWENTY-FIFTH N. Y. INFTY.,
Wolf Run Shoals, Va., December 6, 1862.

Lieutenant R. C. SCHRIBER,

Acting Assistant Adjutant-General:

SIR: I have the honor to report, in compliance with instructions from headquarters provisional brigades, that I arrived at this post day before yesterday with my regiment, the One hundred and twenty-fifth New York, relieving the Fourteenth Regiment Vermont Volunteers. I found, on my arrival here, about 40 of the Sixth Ohio Cavalry, anyone section of the Keystone Battery. Colonel Nichols, Fourteenth Vermont Volunteers, gave me such verbal information as was in his power, but, leaving early the following morning, was unable to accompany me to point out the various localities in the vicinity. Upon examination, I find that this position seems to be peculiarly open to attack by a combined body of infantry, cavalry, and light artillery. My camp is the north side of Wolf Run Shoals. Immediately opposite, and completely commanding the north side of the stream, are two earthworks, thrown up by the Confederate forces last spring; one for four and the other for two guns. These works have never been destroyed. There are also remaining extensive rifle-pits, commanding all the approaches to the ford. With the force under my command, it would be injudicious to cross the river and take possession of these heights, placing between me and my line of retreat the Occoquan River. I should, therefore, recommend the destruction of these works, unless it is intended to hold this point, in which case a much larger force will be necessary.

With the small force of cavalry at my disposal, it is impossible for me to patrol the country thoroughly on the south side of the river. It would, therefore, not be difficult for the enemy to concentrate a small