Wushiiipton, Tfov. 5. The rebels feetween Chain Bridge and Minor's Hill fired on our pickets to-day. The extreme pieket? of our army and the rebels in the diroction of Occoqtian, had a fpieodly interview on Sunday. One 01 tho rebels, clairninw to be an inipressed Pennsylvanian, said tnanv regiments had been withdrawn to Richmond and others were expected to follow. The rebels are thought to be building á largo nnmber of flat boata at Quanticn ('reek. The HéralcPs dispatcb says : " A scout from Virginia roports that Beauregard'a army is stationed io the right oi Braddoefc's road, between Fairfax and Centrcville, 100,000 strong, with two-hundred pieces of artillery out in difierently mnnned, and cenoóniera 6ndiseiplined. The Qüarterraastcr's Departroent is dfáoieot in wngoas, and rnany of th troops are bwrefoot. The Virjginia iroops aro diapirited. Ttose Whose term of ctilifi'inent has expired will not re eoliet, nnd desert every day."