gusn; Arnold's company, D, Second Artillery, two 13-pounder James rifle guns, two 6-pounder guns; Ayres' light company, E, Third Artillery, two 10-pounder Parrott rifle guns, two 12-pounder howitzers, two 6-pounder guns; Griffin's battery, D, Fifth Artillery, four 10-pounder Parrott rifle guns, two 12-pounder howitzers; Edwards' company, G, First Artillery, tow 20-pounder and one 30-pounder Parrott rifle guns. The Second Regiment Rhode Island Volunteers had with it a battery of six 13-pounder James rifle guns; the Seventy-first Regiment new York Militia two of Dahlgren's boat howitzers, and the Eighth Regiment New York Militia a battery of six 6-pounder guns. The men of this last-named battery having claimed their discharge on the day before the battle because their term of service had expired, the battery was thrown out of service.

The whole force of artillery of all calibers was, therefore, forty-nine pieces, of which twenty-eight were rifle guns. All of these batteries wee fully horsed and equipped, with the exception of the two howitzers of the Seventy-first Regiment New York Militia, which were without horse, and were drawn by drag-ropes, manned by detachments from the regiment.

General McDowell's disposition for the march from Centreville ont he morning of the 21st instant placed Tidbal's and Greene's batteries (eight pieces) in reserve, with the division of Colonel Miles, to remain at Centreville; Hunt's and Edwards' (six pieces, with the brigade of Colonel Richardson, at Blackburn's Ford; and Carlisle's, Ayres', and the 30-pounder eleven pieces), with the division of General Tyler, at the stone bridge; Ricketts, Griffin's, Arnold's, the Rhode Island, and Seventy-first Regiment batteries (twenty-four pieces) accompanied the main column came in presence of the enemy, after crossing Bull Run, I received from General McDowell, in person, direction to superintend the posting of the batteries as they severally debouched from the road and arrived upon the field.

The Rhode Island Battery came first upon the ground, and took up, at a gallop, the position assigned it. It was immediately exposed to a sharp fire from the enemy's skirmishes and infantry posted on the declivity of the hill and in the valley in its immediate front, and to a well-sustained fire of shot and shell from the enemy's batteries posted behind the crest of the range of hills about one thousand yards distant. This battery sustained in a very gallant manner the whole force of this fire for nearly half and hour, when the howitzers of the Seventy-first New York Militia came up, and went into battery on its left. A few minutes afterwards Griffin brought up his pieces at a gallop, and came into battery about five hundred yards to the left of the Rhode Island and New York batteries.

Ricketts' battery came up in less than half an hour afterwards, and was posted to the left of and immediately adjoining Griffin's.

The enemy's right, which had bee wavering from the moment Griffin opened his fire upon it, now began to give way throughout its whole extent and retire steadily, his batteries limbering up rapidly, and at a gallop taking up successively two new positions farther to his rear. The foot troops on our left, following up the enemy's retiring right, soon left our batteries so far in our rear that their fire was over the heads of our own men. I therefore directed the Rhode Island Battery to advance about five hundred yards in front of its first position, accompanied it myself, and saw it open fire with increased effect upon the enemy's still retiring right.