On the 29th, two days after General Fremont’s departure from St. Louis, General Price commenced the evacuation of Lexington, leaving a small force as a guard. On the 7th of October, General Fremont left Jefferson City, marching in the direction of Sedalia, for the purpose of attacking the rebel commander at the earliest opportunity. On the 16th, two hundred and twenty men of the First Missouri Scouts, under Major F. J. White, surprised the rebel garrison at Lexington, and recaptured the place, with the Federal sick and wounded there, together with two pieces of cannon, a quantity of guns, pistols and other articles which the rebels threw away in their flight. The garrison numbered three hundred men. The victorious troops found the inhabitants in a deplorable condition. Some portions of the town had been plundered of everything that could be appropriated, and many persons were suffering for the necessaries of life. It was a painful scene, and formed one of those early pictures of the war which have since been multiplied so fearfully in the border States. On the 1st of November, General Fremont, then at Springfield, entered into an arrangement with General Price, to facilitate the exchange of prisoners, agreeing to release any who had been made prisoners “for the mere expression of political opinions;” and providing also that “the war in future be confined exclusively to the armies in the field.” Armed bodies, unauthorized by the commanders, were to be disbanded, and persons guilty of violence and lawless acts were to be subject to trial by courts-martial. This agreement was signed by Major Henry W. Williams and D. Robert Barclay, Esq., for General Price, and J. H. Eaton, Assistant-Adjutant-General, for General Fremont. A proclamation, announcing this negotiation, was accordingly published on the first of November. The next day, General Fremont received from the Department at Washington, an order relieving him from his command. General David Hunter was appointed to the Department of Missouri, temporarily as his successor. General Fremont returned to St. Louis, and soon afterwards reached New York city, where he awaited the orders of the Government. The Federal army was now withdrawn from the south-western portion of the State, and the whole of that vast field was reoccupied by the insurgent forces, and thousands of recruits were gathered into their ranks. On the 4th of November, the antagonist forces were commanded as follows:—General Hunter, 5,000; General Sigel, 4,000; General Ashboth, 4,500; General McKinstry, 5,500; General Pope, 4,000; General Lane, 2,500; General Sturgis, 1,000. The rebels under General Price numbered 15,000; under General McCulloch, 7,000.