The raising of the siege brought Burnside into communication with Cumberland Gap, and he learned that Major-General John G. Foster was at Tazewell, under orders to relieve him of the command of the department. This was in apparent accord with the wish which Burnside had expressed, [Footnote: _Ante_, vol. i. pp. 527, 528.] but as action had been postponed it was reasonable to expect that further consultation would be had before he should be relieved, and that Grant's judgment would be asked in regard to it. After the controversies which followed the battle of Fredericksburg, Halleck was habitually unfriendly to Burnside, and we have seen how uniformly a wrong interpretation was given to the events of the current campaign. Foster's appointment to succeed Burnside was dated the 16th of November, [Footnote: Official Records, vol. xxxi. pt. iii. p. 166.] and he had been in Kentucky or near Cumberland Gap during the siege of Knoxville. The day the order was made relieving Burnside was that on which he was battling with Longstreet at Campbell's Station, holding him at bay in the slow retreat upon Knoxville, where he arrived on the 17th. On this morning Grant was writing him, "So far you are doing exactly what appears to me right," [Footnote: _Id_., p. 177.] and this was written after the receipt of Dana and Wilson's full dispatches of the 13th and 14th, as well as Burnside's of the 13th. [Footnote: _Id_., p. 138.] Yet so strangely was the same information misread by Halleck, that on the 16th he was telegraphing Grant that Burnside was hesitating whether to fight or retreat out of East Tennessee. "I fear he will not fight," he added, "although strongly urged to do so. Unless you can give him immediate assistance, he will surrender his position to the enemy." [Footnote: _Id_., p. 163. This dispatch of Halleck seems to have been called out by one of Dana to Stanton on the 14th in which he said, "Burnside has determined to retreat toward the Gaps." (Official Records, vol. xxxi. pt. i. p. 259.) Halleck failed to interpret this in connection with one of the 13th in which Dana had stated alternate lines of retreat, "if finally compelled," and Burnside's judgment in favor of the line of Cumberland Gap in such last resort rather than toward Kingston. (_Ibid_.) Dana had fully conveyed, however, Burnside's determination to hold Knoxville "as long as possible," and his reasons for making a stubborn fight there. By failing to keep this in mind, the Secretary and General-in-Chief became unnecessarily agitated, and forgot in their conduct what was due to Grant almost as much as what was due to Burnside.] On the next day Burnside entered Knoxville, where fortifications had been hurriedly built, and the siege began. The heroic defence of Knoxville lasted three weeks, and when Longstreet withdrew toward Virginia, the successful general learned that he had been removed from command at the very moment he was completing, with