CHAPTER XXIII. GRANT'S OCCUPATION OF MISSISSIPPI. The Slavery Question .-- A Generous Offer .-- A Journalist's Modesty .-- Hopes of the Mississippians at the Beginning of the War .-- Visiting an Editress .-- Literature under Difficulties .-- Jacob Thompson and his Correspondence .-- Plans for the Capture of Vicksburg .-- Movements of General Sherman .-- The Raid upon Holly Springs .-- Forewarned, but not Forearmed .-- A Gallant Fight..