measles, mumps, and other diseases to which unseasoned troops are subject.
About 1 a. m., July 18th, Johnston received a telegram from Adjutant-General Cooper informing him that Beauregard was attacked, and that to strike the enemy a decisive blow a junction of all their effective forces was needed; and directing him, if it was practicable to make the movement, to send his sick and baggage across to Culpeper Court House, but, in all arrangements, to exercise his own discretion. A half hour later, a telegram from Beauregard informed Johnston of his urgent need for the aid he had promised him in the emergency now arrived. Confident that the troops under his command could render no service in the valley so important to the Confederacy as preventing a Federal victory at Manassas Junction, Johnston unhesitatingly decided to hasten to that point with his whole army, the only question being whether to first attempt to defeat Patterson, or, by a secret movement, elude him. The latter course he considered the quickest and safest, if it could be accomplished. He relied on Stuart to furnish him the means of judging whether this could be done, while his troops were preparing to march. The Federal cavalry, chiefly regulars, had the advantage in arms and discipline, but kept close to the infantry; Stuart, on the contrary, held his men far in advance of the Confederate infantry camps and kept his pickets and scouts near the enemy, and by so doing could quickly learn of their movements, at the same time concealing his own. His report to Johnston showed that at 9 o'clock of the 18th, Patterson had not advanced from Smithfield, a point so far from Johnston's road to Manassas that Patterson could neither prevent nor delay his march. Stuart's information proved the expediency of moving as soon as possible.
Johnston had, at that time, at Winchester, some 1,700 sick men. If he waited to remove these to Culpeper Court House, it would cause a delay of days when hours were of importance. Therefore he provided for these in Winchester, leaving for their defense the militia brigades of Carson and Meem, which were quite strong enough to defend the place and the district. Moreover, there was no doubt but that Patterson would follow, with his main body, the movement to Manassas, as soon as he discovered it; but to delay that discovery, Stuart was instructed
