ONE OF FLOYD’S PERFORMANCES. – It will be remembered that Floyd, during his [unimpeded?] career of larceny and treason, found a number of the heaviest guns belonging to the United States which could not be readily shipped to the South, nor put into any other position where they would be unlikely to do that section injury, and that, as a last resort, he [condemned?] and sold them as old iron. A [Paterson?] firm bought a number of them for $20 per ton. Upon coming to inspect them they were found worth, as manufactured [iron?] alone, three times the price paid for them. Their hardness was such that it was found impossible to break them up for the furnace by the ordinary means, and a few of them were finally wrenched to pieces in a lathe. The remainder were repurchased for Government yesterday by a commission from the War Department, and found to be sound in every particular.