-The Fredericks burg correspondent of the i hiladel pina Inquirer saya : " tlie pontoon bridge across the Raópahannöek, ai this place, is one of the greatest yivoutions oi the age. The pieces are num bered, and, togethcr w'ith the guttf percha floats, aro carried h-om atream to stream. The corps attachod to tht pontoon havo become so perfect h tbeir Inving of tho bridge, that o et rearo, tho width of the Tïnppahannock, can be croesed by the bridge in a feiv minutes. To have just witnessed some practico with anótfier bridge than that already luiil down, and tho performance is really woüderful. Tho government is now repairing tho railroad bridge over tho liappahnnnock, an'l in o few days tho cars will bo enabled to run from Aq'iia Creek into tho city af Früdcricksburg."