An Incident at Fort Sumter. – One of the Baltimoreans who recently returned from Fort Sumter details an impressive incident that took place there on Major Anderson taking possession. It is known that the American flag, brought away from Fort Moultrie, was raised at Sumter precisely at noon on the 27th ult., but the incidents of that “flag raising” have not been related. It was a scene that will be a memorable reminiscence in the lives of those who witnessed it. A short time before noon Major Anderson assembled the whole of his little force, with the workmen employed on the fort, around the foot of the flag-staff. The national ensign was attached to the cord, and Major Anderson holding the end of the lines in his hands knelt reverently down. The officers, soldiers and men clustered around, many of them on their knees, all deeply impressed with the solemnity of the scene. The chaplain made an earnest prayer – such an appeal for support and encouragement and mercy as one would make who felt that “man’s extremity is God’s opportunity.” As the earnest, solemn words of the speaker ceased, and the men responded Amen, with a fervency that perhaps they had never before experienced. Major Anderson drew the “Star Spangled Banner” up to the top of the staff, the band broke out with the national air of “Hail Columbia,” and loud and exultant cheers, repeated again and again, were given by the officers, soldiers and workmen.