All these commands were obeyed. So excellent were the dispositions of the different officers in command of the troops, depots and gunboats, and so thorough was the warning of the approach of the enemy, that almost everything was saved, and but a small amount of stores was destroyed to prevent them from falling into the hands of the enemy. General Stoneman’s communications with the main army being cut off, he fell back upon White House Station, thence to Yorktown, when White House was evacuated.

On the twenty-sixth instant orders were sent to all the corps commanders on the right bank of the Chickahominy to be prepared to send as many troops as they could spare on the following day to the left bank of the river. General Franklin received instructions to hold General Slocum’s division in readiness by daybreak on the twenty-seventh, and if heavy firing should at that time be heard in the direction of General Porter, to move at once to his assistance without further orders. At noon, on the twenty-sixth, the approach of the enemy, who had crossed above Meadow Bridge, was discovered by the advanced pickets at that point, and at half-past twelve in the afternoon they were attacked and driven in. All the pickets were now called in, and the regiment and battery at Mechanicsville were withdrawn.

About three o’clock in the afternoon the enemy formed his line of battle, and came down upon our troops like a torrent—attacking the entire line. McClellan, anticipating a fierce onset, was prepared for such an event, and gave him a warm reception. Our artillery occupied positions commanding all the roads and open ground. Timber had been felled, rifle-pits dug, and the infantry were under cover of the thick woods. All remained quiet until the rebel mass came rushing on—yelling as they came—within a short distance of our line, when every battery and division opened simultaneously a most destructive fire, which drove the enemy back with tremendous slaughter. Several other attacks were made on our lines during the afternoon, which proved disastrous to the enemy. At nine o’clock in the evening the firing ceased, the action having lasted six hours.

During the night the heavy siege guns and wagons were removed to the right bank of the Chickahominy, and most of the troops withdrawn, unknown to the enemy. About noon the next day another general engagement came on, and after seven hours hard fighting the left flank of the Federal line was turned, and they were driven from their position.

General McClellan says: “About seven o’clock in the evening they threw fresh troops against General Porter with still greater fury, and finally gained the woods held by our left. This reverse, aided by the confusion that followed an unsuccessful charge by five companies of the Fifth Cavalry, and followed as it was by more determined assaults on the remainder of our lines, now outflanked, caused a general retreat from our position to the hill in rear overlooking the bridge. French’s and Meagher’s brigades now appeared, driving before them the stragglers who were thronging toward the bridge. These brigades advanced boldly to the front, and by their example, as well as by the steadiness of their bearing, reanimated our troops and warned the enemy that reinforcements had arrived. It was now dusk. The enemy, already repulsed several times with terrible slaughter, and hearing the shouts of the fresh troops, failed to follow up their advantage. This gave an opportunity to rally our men behind the brigades of Generals French and Meagher, and they again advanced up the hill, ready to repulse another attack. During the night our thinned and exhausted regiments were all withdrawn in safety, and by the following morning all had reached the other side of the stream.”

A despatch from General McClellan to Secretary Stanton, on the twenty-eighth, tells a sad story, a part of which I quote:

“Had I twenty thousand, or even ten thousand fresh troops to use to-morrow, I could take Richmond; but I have not a man in reserve, and shall be glad to cover my retreat, and save the material and personnel of the army. If we have lost the day, we have yet preserved our honor, and no one need blush for the Army of the Potomac. I have lost this battle because my force was too small. I again repeat that I am not responsible for this, and I say it with the earnestness of a General who feels in his heart the loss of every brave man who has been needlessly sacrificed to-day.

“In addition to what I have already said, I only wish to say to the President that I think he is wrong in regarding me as ungenerous, when I said that my force was too weak. I merely intimated a truth which to-day has been too plainly proved. If, at this instant, I could dispose of ten thousand fresh men, I could gain the victory to-morrow. I know that a few thousand more men would have changed this defeat to a victory. As it is, the Government must not and cannot hold me responsible for the result.

“I feel too earnestly to-night. I have seen too many dead and wounded comrades to feel otherwise than that the Government has not sustained this army. If you do not do so now, the game is lost. If I save this army now, I tell you plainly that I owe no thanks to you, or to any other persons in Washington. You have done your best to sacrifice this army.”

While the battle of Gaines’ Mill was in progress, I was despatched to several hospitals remote from the direct line of communication, with orders to the surgeons, nurses, and such of the patients as could walk, to take care of themselves as best they could, for no ambulances could reach them; that the army was retreating to the James River, and if they remained longer they would fall into the hands of the enemy.