I have seen the flag at the Georgia DNR some years ago and measured it too. There is much of the flag missing but I would think that its orignial size replicates those existing flags for Bowen's Division at Vicksburg (which had blue fields rather than red).

Also - the flag was somehow hidden at Vicksburg and smuggled out I think - to be taken at Lookout Mountain later that year as Gerald states.

Greg Biggs