accompanying map, the commanding heights approximately laid down and marked A, 1, a, b, c, d, e, f, g, h, i, k, l, 13 m, 14, being occupied by first and batteries.

This line would be about three miles longer than the existing one in the environs of the city, but its entire cost would not, probably exceed the damages which would have to be paid in constructing the additional batteries and rifle-pits of the shorter line, where valuable grounds would have to be occupied, and many buildings demolished to open the fire of the works. This longer line being exterior to Druid Hill Park, would prevent its dense forest being occupied by an enemy, or its possible destruction to prevent a sortiet by the enemy, from its cover, upon the present line (if retained) of defenses between Forts 5 and 7. This proposed line would be removed a mile or more from the outskirts of the city, as would be the case with the present line, an advantage more than compensating for the additional three miles of development and increased garrison.

In any event, until other defenses are provided, we would urge that all repairs essential to defense, be made to the existing forts; that all guns be mounted, and additional artillery be provided, particularly field batteries and siege rifled guns; that all the magazines be supplies with 100 rounds for each piece, and that the garrisons, of whatever arm, be drilled till they become expert in the service of the guns. Without these precautions, forts, guns, and garrisons will be of little avail in the defense of the city. In Forts Marshall and Federal Hill, the two best and largest works, there are extensive would drive every man from the service of the guns, and endanger the magazines. The means for quickly demolishing these buildings on the approach of danger, should be provided. Though they ought never to have been built within the works, yet being there, and a great convenience to the garrison, we would recommend their destruction till the works are liable to attack.

Respectfully submitted.

GEO. W. CULLUM,

Lieutenant-Colonel of Engineers, Brigadier-General.

GEO. THOM,

Colonel, Aide-de-Camp, Major of Engineers.

MONOCACY, July 31, 1864.

Major General L. WALLACE:

Major-General Emory is here awaiting the arrival of his wagon train. We have sent out cavalry and infantry to cover the Georgetown pike. By the disgraceful conduct of Lieutenant Van Ness, of Third New Jersey Cavalry, in charge of detachment guarding the Potomac from mouth of Monocacy to Point of Rocks, 1 man was killed, [and] a lieutenant [and] 15 men, Eighth Illinois Cavalry, captured near Noland's Ferry yesterday by Mosby's thieves. It is reported they captured about 200 horses from citizens on this side. Colonel Clendenin reports the conduct of the lieutenant as cowardly in a superlative degree. No enemy on this side Potomac in this department at latest advices. General Averell reported fighting McCausland at McConnellsburg, Pa., at 8 a. m. to-day; drove