In terminating my report I desire to express the hope that the labors of the officers of the Medical Department may be made more and more worthy of the high mission which has been confided to them.

I am, sir, very respectfully, your obedient servant,

WILLIAM A. HAMMOND,

Surgeon-General U. S. Army.

OFFICE OF THE SIGNAL OFFICER,

Washington, November 10, 1862.

Honorable E. M. STANTON,

Secretary of War:

SIR: The order of the Secretary of War requiring the annual report of the signal officer was received by me a few days since, on resuming the charge of my office in Washington, after some months" service in the field with the Army of the Potomac.

The period within which the report must be rendered will permit of a summary only. A report in detail will be prepared at this office, and, with accompanying documents, will be laid before the Secretary of War as soon as it can be completed.

The total number of officers detailed and under instructions as acting signal officers in the different military departments of the United States since the date of my last annual report (November 30, 1861) has been 199. Of this number 146 have been retained for signal service. They have been distributed as follows;

As the signal corps-

Army of the Potomac....................................... 48

Army of the Mississippi................................... 35

Department of North Carolina.............................. 11

Department of South Carolina.............................. 15

Fortress Monroe, Va....................................... 10

Department of the Gulf.................................... 9

Yorktown, Va.............................................. 2

On special service, or awaiting orders.................... 16

The corps has served under different rules with different armies. With some it has been broken in small parties, scattered with the various divisions; with others the officers have been kept together, and have acted under a chief, who orders all movements. Experience has seemed to indicate that the duties of the corps with an active army are most efficiently rendered when these services are controlled by one officer, who, properly informed at headquarter of movements contemplated or making, understanding takes steps to place his officers where their labors may be most useful.

REPORTS FROM DETACHMENTS.

The detachments of the corps with the armies in Virginia and Maryland, in North Carolina,in South Carolina, and in the Department of the Gulf have had the fortune to be with armies which have changed but little in organization. The reports from these detachments have been steadily favorable.

The detachments serving in the Valley of the Mississippi and in the departments west of the Alleghanies have kept their organization, and rendered such service as they could under great difficulties.

The forming and control of these parties was, of necessity, given to young officers of volunteers, themselves hurriedly instructed and