In Foster's department the same energy was directed toward improving the communication with Chattanooga. The hull of the light-draught steamboat which Colonel Byrd had found under construction at Kingston was taken as a model, and two more were put on the stocks. [Footnote: _Ante_, vol. i. p.523. Official Records vol. xxxi. pt. iii. p. 483.] Pontoon bridges were prepared for use at different points on the river. Lumber was cut to rebuild the great railway bridge at Loudon and the long trestle at Strawberry Plains. The little train of "twenty-odd cars" which Burnside had captured was carefully guarded and kept running on the only bit of railroad in East Tennessee that was now open, viz., that from Loudon through Knoxville to Strawberry Plains. Herds of cattle were threading mountain paths to avoid the deep mud of the wagon roads from Kentucky, and on those roads desperate but too often fruitless efforts were making to push forward some wagon-loads of shoes and clothing. In the consultations at Knoxville Foster had plainly stated his own conviction that the only wise course was to abandon the thought of aggressive warfare until spring; to station the troops so as to cover Knoxville, but to select their positions chiefly with reference to collecting forage and breadstuffs; to send all unnecessary animals to the rear and in every way to simplify to the utmost the problem of carrying the army through the winter, preserving it for active use when the change of season and the improvement of the railway line should make regular supplies possible. [Footnote: Official Records, vol. xxxi. pt. i. pp. 281 _et seq_.] Grant listened and suspended his judgment till he had examined the situation for himself. An accident to General Foster had increased the complication of affairs. He was occasionally suffering from lameness resulting from an old wound in the leg, and had found on his first journey over the mountains that he was in danger of being disabled by it. Within a fortnight after he reached Knoxville, his horse fell with him in passing over some slippery rocks, and caught the wounded leg under him. [Footnote: _Id_., pt. iii. p. 502.] This completely disabled the general for active field service, and on the advice of his surgeon he asked to be relieved. This request was forwarded on the 26th of December, and Grant had been notified of it on the same day. It could not be acted on at once, and during the few weeks that Foster remained at the head of the department, he was obliged to remain in Knoxville, entrusting to General Parke, as senior officer, the active command of combined movements in the field.