Early was fully assured, and asked if Wright and Hunter were not strong enough to attack him. You need not send any troops back until the main force of the enemy is known to have left the Valley. Is Wright still where he can act in conjunction with Hunter? If the two can push the enemy back and destroy railroads from Charlottesville to Gordonsville, I would prefer that service to having them here.

U. S. GRANT,

Lieutenant-General.

HEADQUARTERS CHIEF ENGINEER OF DEFENSES,
Washington, July 22, 1864.

Major General C. C. AUGUR,

Commanding Department of Washington:

GENERAL: In compliance with your directions, I have caused the ground occupied by the rebel troops to be surveyed and the locations of camps noted, and send you a sketch* herewith; also a report of Lieutenant Oberteuffer and Mr. hergesheimer (U. S. Coast Survey) on the subject. No very definite statement of actual numbers was obtained, but it is certain that, besides the 1,500 calvary which approached Tennallytown, on the Rockville road, and the calvary which encamped at Silver Spring, very heavy bodies of infantry came up on the Seventh-street road, bivouacking from Silver Spring to Batchelor's, two miles distant. Twenty pieces of artillery are known to have been brought up to Silver Spring and five pieces were with McCausland's command. The belief that a very considerable force advanced from Rockville to Leesborough on Monday was founded by myself upon observations made from Fort Reno on Monday of dust; not upon any given appearance of dust at one moment, but upon the permanence, of its exhibition at the same points, indication the continued occupation appeared on the road from Rockville to Leesborough on Monday; indeed they were seen by me from about 8 a. m. till 2 p. m., and observed by others during the rest of the day.

The statement of persons in the vicinity confirm the observations from Fort Reno, as they generally give to the time the columns were passing given points, both in advance and retreat, a duration of nearly twelve hours. The line marked "rebel skirmish line" was marked by the hasty cover of fence rails, earth, &c., thrown up, as well as by the remnants of cartridges, ammunition-boxes, and other relics. On the other side of the road in the woods opposite Silver spring a line of relics has been traced which has been supposed to have been a line of battle, but which Lieutenant Oberteuffer considered a mere line of communication with the cavalry camp.

I am, very respectfully, your most obedient,

J. G. BARNARD.

P. S. -By orders from headquarters U. S. Army, I leave to-morrow to report to General Grant. During my absence Colonel Alexander, it is presumed, will act as chief engineer of the defenses of Washington.

---------------

*Not found.

---------------