Not only was Grant left upon the defensive with a force too small to permit aggression of any kind on his part, but even this scant force was rapidly and very dangerously depleted by orders from Halleck's Washington headquarters. The Confederates and guerrillas were daily threatening his communications and frequently attacking his defensive detachments in force. He was confronted on the south by an effective force of 35,000 men under Van Dorn and Price, threatening Memphis, Corinth, Bolivar and other points. Grant's concern for the safety of Memphis, isolated as that post was by the Confederate occupation of Grand Junction--between Memphis and Corinth--was lightened only by the fact, as he himself suggestively put the matter, that "it was in Sherman's hands." Under this stress of circumstances, and with extraordinary disregard of what disastrous consequences there might be involved, Halleck on the fourteenth of August ordered Grant still further to weaken himself by sending two more divisions to Buell on his tedious march eastward. Again on the second of September, Grant received orders to send still further reinforcements to Buell, and two days later Gordon Granger's division was detached and sent, by orders from Washington, to Louisville. On the twenty-second Colonel Rodney Mason, whom Grant had forgiven for arrant cowardice at Shiloh, made a dastardly surrender of Clarksville with half a regiment or more. Thus the one commander who had thus far shown himself capable of conceiving campaigns and conducting them to success, was left with a totally inadequate and constantly diminishing force, to waste his time in guarding a vast territory while Bragg was marching from Rome, Georgia, with a strong Confederate army toward Chattanooga, meaning to seize that position before Buell could get there. In his "Memoirs" General Grant gives expression to his regret that he was not permitted to move, instead of sitting still, at a time when even with the depleted force under his command, he still felt confidant of his ability to crush and destroy Bragg's force, thus forestalling and rendering unnecessary the very severe and bloody campaigns which were destined to follow for lack of such a timely blow.