From the southwest.
An official dispatch, received yesterday from Chattanooga, confirms the report published yesterday of the retreat of Rosecrans from Iowa on the 12th inst., and the subsequent occupation of the place by Gen. Price's army. The enemy abandoned several hundred thousand dollars' worth of army stores. The same dispatch also mentions that Rosecrans and part of his army had arrived at Nashville.A gentleman just from Northern Alabama says that Rosecrans is in full retreat towards Athens Tenn. He has been seriously annoyed by guerrillas since his departure from Pittsburgh Landing and Florence, the whole of Middle Tennessee literally swarming with partisan rangers. From every hill top, and in every vale where the forests offer the slightest concealment, the fleeing Yankees are made to bite the dust. On Tuesday of last week a portion of Rosecrans's command was ambuscaded in Middle Tennessee, and nine instantly killed, and some 25 or 30 wounded.
