These lines were in constant use, transmitting messages of the first importance-the Chickasaw Landing and Haynes' Bluff lines until relieved by the telegraph, and the line to Young's Point till the surrender of Vicksburg.

Lieutenant Sampson deserves particular mention for the manner in which he conducted affairs as his station, at General Grant's headquarters.

During the occupation and fortification of Haynes' Bluff, a detachment in charge of Lieutenant Sample was directed to report for duty to Major-General Washburn, commanding that post; reconnoitered lines to advance cavalry pickets and to Big Black River railroad bridge, and pronounced communication by signals practicable; but General Osterhaus, commanding at bridge, not desiring communication, General Grant directed that the line should not be established, as he had other use for the signal force. A party was then ordered to open a line from General McPherson's headquarters (from which communication was had with General Grant by telegraph) to Major-General Herron, near Warrenton. This line was opened and used for a time, when another was opened from General Herron to the gunboats, which remained open and in use until the surrender of Vicksburg. The party with General Washburn were constantly on duty with the troops stationed at different points; reconnoitered the whole country from Haynes' Bluff to Big Black River railroad bridge, where they were at the surrender of Vicksburg.

Captains De Ford, Rose, and McClintock, who were at different times in immediate charge of the corps, have in many instances spoken in the highest terms of the activity and zeal displayed by the officers and men, and of the alacrity with which they performed the duties assigned them, sometimes the most arduous and trying.

To the officers and men of this corps, many of whom are now prostrated by illness from fatigue and exposure during the campaign, but who bore up manfully until the great object was obtained; who, fresh from the camp of instruction, there performed their first duty as signal officers, and who, under the most trying circumstances, unaided by previous experience, have, by persevering toil, overthrown or turned aside obstacles which would have appeared discouraging to more experienced officers, and who have patiently and bravely performed their whole duty, I am under the highest obligations.

I have the honor to be, sir, very respectfully, your obedient servant,

O. H. HOWARD

Captain and Chief Signal Officer.

Lieutenant Colonel John A. RAWLINS,

Assistant Adjutant-General, Department of the Tennessee.

Numbers 7. Reports of Major General John A. McClernand, U. S. Army, commanding Thirteenth Army Corps, of operations March 30-June 17, with resulting correspondence.

HEADQUARTERS THIRTEENTH ARMY CORPS,
Battle-field, near Vicksburg, MISS., June 17, 1863.

COLONEL: I have the honor to submit the following report of the principal operations of the forces with me since March 30 last, in compliance with instructions from department headquarters to that effect.