What they left at Cumberland Gap.
--A correspondent of the Montgomery Advertiser, writing from Cumberland Gap, states that the destruction of Federal property at that point amounted to some two hundred thousand dollars, among which were seventy-five thousand dollars' worth of small arms, four large guns, besides the magazines, containing a large amount of cartridges, bombs, &c., a considerable quantity of which fell into our hands from having failed to ignite. Ten thousand dollars' worth of good harness was left untouched; also, spades, picks, axes, and many other articles.