near Yorktown and discovered that the enemy had left, and at 6 o"clock a portion of them were visible about two miles from Yorktown on the road to Williamsburg.

Very respectfully, your obedient servant,

T. S. C. LOWE,

Chief Aeronaut.

It was known by all who had an opportunity of knowing that the enemy continued their works and kept up appearances until the night of the evacuation, and even kept their batteries firing until after midnight. Their barracks and tents, many of them new, were all left standing. Medical stores and ammunition (some destroyed and thrown into the river) were left, which it would seem would not have been the case if the evacuation had been long premeditated.

It is true army wagons were daily seen plying between Yorktown and Williamsburg, and so reported, but it was impossible to say which way they were loaded.

On the afternoon of the 4th I received orders to move everything pertaining to my department by water, with General Franklin's command. Judging from my orders, it would seem that the battle of Williamsburg was not expected.

The balloons were accordingly taken to West Point, and one was inflated on the balloon boat and used by General Franklin during his stay at that place, where reports were made to him of the position and movements of the enemy. After this we moved by water to White House Landing, the balloon boat being the first to land, and was even some distance, ahead of the gun-boats, while the first night the balloon guard was the advance picket on the river bottom.

On the 18th of May I received orders to accompany General Stoneman, who was then some distance in the advance. We arrived near the Chickahominy on the morning of the 20th, and on the following morning, accompanied by General Stoneman, I ascended, and there had a distant view of Richmond, the general being the first to point out the city as we were rising. After ascertaining the location of the enemy, General Stoneman advanced his forces to Gaines" Hill, and there rested until the main portion of the enemy, which was still some distance in the rear, came up, while in the meantime the balloon was kept, in constant use, and all the movements of the enemy were reported.

On the 25th of May the balloon proved of great advantage, and I copy the following memorandum from my notebook respecting the observation made:

GAINES" HILL, May 25, 1862.

This has been a fine and important day. General Stoneman ascended with me to an elevation of a thousand feet; had a splendid view of the enemy's country; discovered a force of the enemy near New Bridge, concealed to watch our movements. The general then took two batteries and placed them to the right and left of Doctor Gaines" house, and caused the enemy to retreat for at least a mile and a half, while he remained in the balloon with me, directing the commanders of the batteries where to fire, as they could not see the objects fire at. The general then went to Mechanicsville and drove the enemy from that position, while I remained up in the balloon to keep up appearances and to see if a larger force opposed him.

After descending, General Stoneman was heard to say, in the presence of several gentlemen, that he had seen enough to be worth millions of dollars to the Government.

It is certain that he is too keen an observer and too able an officer to be insensible of the advantages of so superior and accurate means of observation asOne of the principal objects of General Stoneman in driving the rebels from the banks of the Chickahominy was to enable him to move to Mechanicsville