Oglethorpe goes to Charlestown, South Carolina, to open his Commission--Comes back to Savannah--Gives encouragement to the Planters--Returns to Frederica--Excursion to Coweta--Forms a Treaty with the Upper Creeks--Receives at Augusta a delegation of the Chickasaws and Cherokees, who complain of having been poisoned by the Traders--On his return to Savannah is informed of Spanish aggressions, and is authorized to make reprisals,.