MR. PRESIDENT:—I have the honour to report, for the information of your Excellency, that General Imboden has destroyed the bridges on the Baltimore and Ohio Railroad over Evarts’s Creek, near Cumberland; the long bridge across the Chesapeake and Ohio Canal below Cumberland; the iron bridge across the North Branch of the Potomac, with the wooden trestle adjoining it; the double-span bridge across the mouth of Patterson’s Creek; the Fink’s patent iron bridge across the mouth of the South Branch of the Potomac, three spans of 133⅓ feet each, and the wooden bridge over Little Cacapon. All the depots, water tanks, and engines between the Little Cacapon and the Cumberland are also destroyed, with the block-houses at the mouth of the South Branch and Patterson’s Creek. The Chesapeake and Ohio Canal, about two miles above Old Town, where the embankment is about forty feet high, has been cut, and General Imboden reports that when he left it the entire embankment for about fifty yards had been swept away. A similar crevasse with like results was also made in the canal about four miles from Old Town. Lieutenant-Colonel White, of the cavalry, has also cut the Baltimore and Ohio Railroad, east of the Point of Rocks. General Milroy has abandoned the south side of the Potomac, occupying Harper’s Ferry with a picket, and holds the Maryland Heights with about eight thousand men. General Ewell’s corps is north of the Potomac, occupying Sharpsburg, Boonsborough, and Hagerstown. His advance cavalry is at Chambersburg, Pennsylvania. The First Division of General A.P. Hill’s corps will reach this vicinity to-day; the rest follow. General Longstreet’s corps with Stuart’s cavalry still occupy the Blue Ridge between the roads leading through Ashby’s and Snicker’s Gaps, holding in check a large force of the enemy, consisting of cavalry, infantry, and artillery. The movement of the main body of the enemy is still toward the Potomac, but its real destination is not yet discovered.... If any of the brigades that I have left behind for the protection of Richmond can, in your opinion, be spared, I should like them to be sent to me. I am, with great respect, your obedient servant, R.E. LEE, General. Several days later, Ewell being now so advanced that support for him was absolutely necessary, Longstreet was withdrawn from the edge of the Blue Ridge. With the First Corps he crossed the Potomac at Williamsport. A.P. Hill and the Third followed, crossing at Shepherdstown. At Hagerstown the two corps united and the resulting column moved northward into Pennsylvania.