Maj. Jed. Hotchkiss, Confederate Military History, a library of Confederate States Military History: Volume 3, Virginia
Clement Anselm Evans, Ed.

[156] mountain region, the dome of the watersheds of northwestern Virginia, covered by a vast and dense forest of large evergreen trees, reaches an altitude of nearly 5,000 feet, so that, naturally, it is at all times a damp and chilly region having a large rainfall. During this particular season the precipitation was very much larger than usual. During most of the months of July and August there was a steady downpour of rain, with intervals of heavy mists. In consequence of these climatic conditions, the whole country became saturated with moisture, and even the graded mountain roads, cut up by the constant passing of heavy army trains, were converted into streams of axle-deep mud, making them practically impassable for vehicles of any kind. The many unbridged streams, swollen by these steady rains, added to the difficulties of transportation. This continuous damp and chilly weather caused a great amount of sickness of every kind among the thousands of unseasoned troops here congregated, until nearly half the army was laid up, in poorly provided hospitals, and the mortality from sickness became very large. Nearly every house in all this sparsely settled country was converted into a hospital, and hospital tents, filled with sick men, were pitched all along the roads to the rear of the armies. Supply trains could not reach the camps, and so for weeks the army was on short and poor rations, and the men, many of them from cities and towns, and most of them unused to exposure and accustomed to all the comforts of good homes, were here forced to pass through an ordeal more trying than that of constant fighting; but they bore all this with uncomplaining courage, wondering why they were not led to action when they could see, from their camps, those of the enemy but a day's march away. On the 1st of September the weather conditions changed, and the dry and hot weather of the early autumn succeeded, with storms at intervals, but the roads became drier so the army could be concentrated and supplies for a few days ahead be gathered at the camps.

The topographical engineer of the army, Capt. Jed Hotchkiss, having completed a detailed map of Tygart's valley, from Valley mountain to Huttonsville, and other arrangements perfected, Loring at last yielded to Lee's urgency for an advance, and on the 8th of September issued confidential orders for a simultaneous movement