About one
o'clock
Soon the sounds of battle were heard far in front , and the step was lengthened . The day was hot , and the road was dusty . Frequently we went at double-quick . About one o'clock we waded the Potomac below Shepherdstown . Beyond the river the march turned northeast -- a rapid march ; many men had fallen out before we reached the river ; now many more began to straggle . All the while the roar of a great battle extended across our front , mostly in our left front . We passed through a village called Sharpsburg .