From the Southside.
Petersburg, July 3.
--A courier to Capt. Milli.
gan, of the Signal Corps, has reached here from Bermuda Hundreds.
A couple of free negroes were sent over to Shirley yesterday.
They returned and report that the enemy and his wagons have left Shirley and gone towards Westover, on the north side of James river, below City Point.
Heavy firing all yesterday afternoon, four miles below City Point.
All the gunboats and transports have disappeared None were visible at City Point.
[second Dispatch.]
Petersburg, July 3.
--Occasional firing has been heard to-day in rear of Westover, Charles City county.
The train of wagons at Berkeley has greatly increased since yesterday.
It extends for miles, and is distinctly seen from Prince George shore.
Some estimate the number at over one thousand.
Several fugitives from McClellan's army were arrested on this side of the river to day. Five have just been brought in and lodged in the Petersburg jail.
Others were arrested near Bermuda Hundreds, and taken to Drewry's Bluff.
All of them say that McClellan is badly worsted.
The enemy abandoned Curlos's Neck, Tuesday night, leaving twenty pieces cannon, several hundred boxes of fixed and other ammunition, and a vast amount of commissary and other stores.
Persons living in the vicinity represent the army as sadly discomfited, broken down, and exhausted.--Many of the Yankees were buried at Shirley, and several of the wounded were left there.
The gun boats are still hovering about Berkeley, and shelling the woods promiscuously. 