operations of that branch of the staff will sufficiently indicate the character and extent of its labors.

These maps were as follows, viz:

1. Of the position of Yorktown and Warwick Creek and River, with the approaches from James, York, and Poquosin Rivers.

2. Of the position of Williamsburg and the approaches and the adjacent country.

3. Of the approaches to Richmond between the Pamunkey and Chickahominy.

4. Of the positions on the Chickahominy.

5. Of the approaches to Richmond from the Chickahominy.

6. Of the position at Harrison's Landing and the approaches and the country adjacent from Malvern Hill to Charles City Court-House.

From these maps and the Coast Survey maps of the James and York Rivers and the State map of Henrico County a very detailed map was prepared in three parts, embracing the country between the James and York Rivers, and extending from Old Point Comfort to Richmond.

Since these maps can present comparatively little of the information required concerning a country that is the scene of military operations, they should be accompanied by a memoir. Notes were collected by me with the object of preparing one, and it was my intention to give so much of the physical geography of the region in which the campaign was carried on and the territory contiguous as was necessary to exhibit clearly the characteristic topographical and hydrographical features; the nature of the soil; its natural growth and degree and kind of cultivation, and the direction and character of the routes of communication, both by land and water. The characteristic features, natural and artificial, of the several positions of Yorktown, Williamsburg, the Chickahominy, Richmond, Malvern Hill, and Harrison's Landing, would likewise have been described.

Continued sickness during the occupation of the position of Harrison's Landing prevented my accomplishing this task, and immediately after the withdrawal of the Army of the Potomac from the peninsula of the James and York Rivers I was, at my own request, assigned to the command of troops, and the division of new troops that I have commanded since that time has occupied all my time.

Besides the officers, Coast Survey assistants, and civil engineers, who constituted the more or less permanent force of the topographical engineer department of the Army of the Potomac, many officers of the Corps of Engineers and of the line of the army and volunteer force served temporarily under my orders. Their names will be found upon the maps prepared from the reconnaissances in which they assisted, but I should not permit the opportunity to pass without acknowledgment of the zeal and efficiency with which the duties assigned them were executed.

Those who served more permanently under my orders were, Lieutenant Colonel W. R. Palmer, Captain H. L. Abbot, First Lieuts. Orlando G. Wagner and N. Bowen, Topographical Engineers; Lieutenant George A. Custer, Fifth Cavalry; Captain James Hope, Second Vermont Volunteers; First Lieutenant Carswell McClellan, New York Volunteers; Messrs. F. W. Dorr and J. W. Donn, assistants United States Coast Survey; Messrs. Fred. Churchill, F. W. Vaughn, H. H. Humphreys, Walter Taylor, civil engineers, and Mr. James McMackin, draughtsman.

I should not omit to mention my indebtedness to Colonel G. K. Warren, Fifth New York Volunteers [now brigadier-general of volunteers, captain