Convinced of the inutility of his own presence at Vicksburg, and preoccupied with the risks threatening his squadron from the unguarded state of the river and its dangerous navigation, it is not wonderful that Farragut, who was the senior of the two flag-officers, thought little of the single ironclad vessel in his neighborhood. He was not prone to exaggerate danger, and his experience had not led him to entertain any high opinion of the enemy's rams. To these circumstances he owed one of the most mortifying incidents of his career. On the 15th of July a reconnoitering expedition was sent into the Yazoo, composed of two vessels of Davis's squadron, accompanied by one of the rams which at that time formed an independent organization upon the upper Mississippi under the command of Colonel Ellet. It was a fortunate move, for to this circumstance was due that the squadrons had any notice of the approach of the Arkansas. The detached vessels met her about six miles within the Yazoo, when a running fight ensued between her and the Carondelet, to the disadvantage of the United States vessel; but the sustained cannonade attracted betimes the attention of the fleet, and the Tyler, a small unarmored boat, after supporting the Carondelet to the best of her ability through the action, preceded the combatants down stream, bringing tidings of the ram's approach. There was not time to raise steam--only to cast loose the guns for action. When the Arkansas reached the fleet her smoke-stack had been so often perforated by the Carondelet's shot that her boilers could scarcely supply any steam. Her speed was thereby reduced to one knot, powerless to ram and scarcely sufficient to steer. At that rate, with the favor also of the current, she passed through the United States vessels, suffering from their successive fires much injury, though not of a vital kind, and took refuge under the guns of Vicksburg. It was a most gallant exploit, fairly comparable in daring to the passage of the Mississippi forts, but resulting in no decisive effect upon the issues of the war.