We have reserved our artillery fire, and have drawn theirs, which consist mostly of field guns, but some heavy rifled 6-in guns. I find no attempt has been made to repair the railroad WEST of Jackson, but that the north and south has been, and cars running. General Parke is now in possession of the north branch, has broken the telegraph wires, and will and once destroy this railroad for miles. I have dispatched Bussey's cavalry farther to the north, on same errand, and other cavalry to the south. I learn that Pearl River Bridge is not repaired, though in process of building. Cars cannot pass it yet. Two common bridges are across Pearl River, near the railroad, which connect travel from the cars, which stop a mile east of Jackson, transferring freight and passengers to wagons and carriages. All the families are away from their houses all round about Jackson, and everything betokens a strong resistance. I would ; like another DIVISION on the road from Champion's Hill to Clinton, to guard the communications and a depot of supplies kept at the railroad bridge on Big Black River. /By our former trip, and the demands of Johnston's army, the country is stripped of food and forage. I have plenty of wagons.

I am,&c.,

W. T. SHERMAN,

Major-General Commanding.

Lieutenant Colonel John A. RAWLINS, assistant Adjutant-General.

Headquarters Fifteenth ARMY CORPS,

Camp before Jackson, July 12, 1863.

General Lauman, in taking to-day, got his line uncovered by skirmishers too close to the enemy's lines and suffered considerably; loss not yet ascertained. Colonel Gresham is reported killed. Lieutenant Adams, of the artillery, was killed the first day, and Lieutenant Nelson,*of the regulars. The ground to the right is so wooded that General Ord has been unable to ascertain Lauman's loss. Johnston evidently intends to make a strong fight at Jackson behind his parapet. He my endeavor to operate outside with Cavalry. With plenty of rifle ammunition, I can make the town pretty hot you alive in.

I have published all the good news to our troops.

W. T. SHERMAN,

Major-General.

Major-General Grant, Vicksburg.

Headquarters Fifteenth ARMY CORPS,

Before Jackson, July 12, 1863-10 a. m.

I gave the enemy's line and town an hour's cannonading this morning with our rifled guns. I have the Canton road(Parke), about 1 1/2 miles from State-house; The Clinton road to the hospital(Steele), and the Raymond road and railroad, to the house where we were May 14. All telegraphs and railroad north and south are broken good, and cavalry is out expecting the damage. I am now maneuvering on the Pearl River to reach the east. Will keep troops well in hand. News from all quarters glorious. As usual, my 20-pounder Parrott guns use too much ammunition. Please send to Big Black River Bridge 4,000 rounds 20-pounder Parrott ammunition; 10,000 6-pounder shells, and 1,000,000

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*Captured, not killed.

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