Gen. Johnston's retreat Grant Pursuing in heavy. Force — the Vicksburg paroled prisoners.
Morton, Miss, July 18.
--Gen. Johnston's army is still slowly falling back.
Up to 4 o'clock yesterday none of Grant's troops, except about 2,000 cavalry, had crossed Pearl river.
Our cavalry is skirmishing with their's beyond Brandon.
Citizens who came out since the evacuation of Jackson, say that the citizens there had sent a flag of truce to Grant formally surrendering the city.
Grant assure them that private property would be respected.
Their cavalry came in at 8 o'clock and took possession.
[Second Dispatch.]
Morton, Miss., July 18.
--Gens. Pemberton, Stevenson, Bowen, Boston, Smith, and Cummings, and all the field officers captured at Vicksburg, have been exchanged.
The men had straggled all over the country.
Gen. Bowen is lying dangerously ill, unable to be brought to Lewis.
Gen. Jackson's cavalry has just returned from Grant's rear.
It captured and destroyed a train of 100 commissary wagons.
It reports an enormous force at Canton.
Grant's army crossed the river in heavy force yesterday and is moving on us.
[Morton, where this dispatch in dated, is on the Southern (Mississippi) Railroad, 79 miles from Vicksburg and 24 from Jackson.] 