Answer. From 4 o'clock until about 11 (I am not exactly confident as to the time of leaving it) my headquarters, as announced in the order of battle on the day previous, were established at the headquarters of the Ninth Corps. At 11 o'clock, or about that time, as near as I can remember, I returned to the headquarters of the Army of the Potomac, which are situated about three-quarters of a mile to the eastward of the headquarters of the Ninth Corps, and are in telegraphic communication with the same headquarters, where I remained during the rest of the day.

Question. How far was that from the scene of action?

Answer. If by the scene of actions is meant the crater of the mine and that portion of the enemy's line in front of it, so far as I have knowledge of the ground, derived from maps, I should suppose that the headquarters of the Ninth Corps were possibly a mile to the eastward of the crater, and my headquarters are three-quarters of a mile, as I stated, beyond that still farther to the east.

Question. Could anything of the action be seen from there?

Answer. Nothing could be seen from any of the points that I occupied.

Question. Did you go farther to the front during the action? If so, where?

Answer. I did not leave the headquarters of the Ninth Corps during the active operations.

Question. Did you not know that there were several positions on our line where you could see the action for yourself, and yet be in as proper a place for you as in General Burnside's permanent camp, and also have full personal communication with Generals Burnside and Ord, and be much nearer General Warren, and likewise have telegraphic communication with the rest of the army?

Answer. I undoubtedly was aware that there were points of the line where I could see more of the action than I could see at the position I occupied, but I was not aware that there was any point where I could see any thing particularly, or on which I could base any orders. I adopted the position I did in consequence of its being a central one, and in telegraphic communication with all parts of the line where officers were stationed with whom it was necessary to communicate, and having a large staff and many communications to receive, and many persons to communicate with,and being there in telegraphic communication I considered it more proper to remain where I announced to the army my headquarters would be and where all information could be sent to me, than to make any change of position as intimated in the question. Besides which, I desire to say to this Court that it has been a matter of policy with me to place myself in such position that my communications made and the replies made thereto should be made in such way as a record could be kept of them, and not be confined to verbal communication, which are often subject to misapprehension and to misconstruction. There undoubtedly was telegraphic communication from General Burnside's headquarters in the field, the fourteen-gun battery as it was called, with the other headquarters in the army.

Question. Did you not have an aide-de-camp with General Burnside during most of the action?

Answer. During a portion of the time I did have Captain Sanders, aide-de-camp, at the headquarters of General Burnside. I sent him there in consequence of not receiving any communication from General Burnside, in the hope that he would be enabled to send me some information.

Question. Was not Captain Sanders sent there before the mine exploded?

Answer. No, sir; he was sent there some considerable time after the mine exploded-that is, upon the duty that I now refer to. I have previously stated to the Court that before the mine exploded I sent two officers to endeavor to explain the delay. One was Captain Jay, and one might have been Captain Sanders, but they returned before the explosion of the mine. After the explosion of the mine I sent Captain Sanders on the duty that I now refer to, which was to remain at General Burnside's headquarters, and communicate to me anything which he could ascertain. I think it further proper to add to this answer to this question, that finding I did not get the information which I desired to have, or which I thought I could have, and fearing that my having an aide-de-camp, the object being to facilitate the trans-