AVo are able to announce on unquestionable authority that Gen. Scott has so far maturod the plans for the war as to inforra the President and Cabinet that the last seeession flag shall be torn down, tlio authority of the Federal Government reinstated on every foot of American soil, and Jeff. Davis hung or driven out of the country, witten eleven months f rom the day when Fort Sumpier teas turrendered. About the 4th of Mareh next he will hand over the Union, safe and sound, to its constitutcd and con3titutional authorities. Old Lundy's Lane takes his time to map out the campaign and put his forces in the best fightiug trim, and tli en he always wins at the time of day when he agrees to. He bas taken the contract to wind up the disunion business within eleven months from the 13th of April, and he toill do it. We undorstand that it is part oi Gen. Scott's plan to oceupy Virginia and Tennesseo completely on or before the 20 th of July. 65,000 North-western troops will move down the Mississippi as far as Mcmphis, under command of Generáis Frcmont and McGlellan, and remain in camp until the sickly season is past, when they will move on toward the Balize, thcre meeting the couquering army of the Eist, and celebrating Washington's birth day in New Orlcans.