...and those immediately surrounding him, were the first attacked. The death of Capt. L. A. Warfield, which I mentioned in my last letter, was followed by that of Capt. J. C. Williams, Aide-de-camp to Gen. Mitchell .--These two cases were followed by the illness of General Mitchell's two sons, both upon his staff, and Captain J. J. Elwell, Assistant-Quartermaster, and then the disease spread so rapidly as to cre...