Mules to Pack Down the Snow

“Bolivar Roberts [Division Superintendent in Carson City, NV] was worried. The success or failure of the Pony Express might easily depend upon its first run. . . .On the first report of a blizzard [in the Sierra Nevada], Roberts had sent riders hurrying to the mountains with strings of pack mules. The mules were to be kept constantly on the move, treading out the trail through canyons or passes where blowing snow was beginning to drift. Even if it took the pony rider a week to reach the summit, the mules must keep the trail open until he passed.”