I don't know if it is the same one you are researching, but Fort Cobb was the name sometimes given to Battery Cobb and Battery Gilmer at the Narrows of the Apalachicola River in Florida. The fort was located about 50 miles up the river from the Gulf of Mexico and was designed to protect the Apalachicola, Flint and Chattahoochee River valleys from attack. Infantry troops were stationed there for a time to protect the guns. The actual location is in what is now Gulf County, not far from the town of Wewahitchka. I know that Georgia troops, including Bonaud's Battalion, were stationed along the Apalachicola River at times. Camp Cobb, mentioned in the above post, was at Quincy, Florida, according to local tradition. Fort Cobb was downriver between Chattahoochee and Apalachicola. I hope this helps!