Shipments of Firearms.—karge quantities of arms and munitions of war continue tb go South from New York, notwithstanding the vigilance of that remarkable man, Superintendent Kennedy. The steamer Jamestown, which, left on Tuesday for Norfolk, had her main deck literally loaded with gun carriages, and rifles in boxes and eases. The former were shippedto the order of Captain Randolph, of Virginia, and were manufactured at Troy. The impression is that their real destination is some point farther South.