Making room for the Army of the Potomac, General Howard marched his Corps toward Jefferson, Maryland. During the early hours of June 25th, General John Reynolds ordered General Oliver O. Howard to send a brigade of infantry along with a battery of rifled guns to report to General Julius Stahel and his cavalry at Crampton's Gap.

On June 26th, General Oliver O. Howard's 11th Corps began to occupy the mountain gaps along South Mountain. His headquarters was located at the Cookerly farm outside of Middletown. General Howard posted one brigade at Crampton's Gap, one at Turner's Gap, and another brigade on the road to Burkittsville and the final brigade on the Hagerstown Road. During the evening General Howard sent a dispatch to General Reynolds that stated that no Confederate force reported to have been seen at Crampton's Gap. General John Reynolds led his 1st Corps to Jefferson, Maryland and would proceed to Middletown the following day.

General Julius Stahel reported to General Reynolds through a dispatch that the whole Confederate Army had passed through Hagerstown and was now in Pennsylvania. General Anderson's Division of General A.P. Hill Corps had passed through Boonsboro on the 25th at around 6 a.m. He also reported that General Ewell's Corps had passed through Hagerstown and was heading toward Harrisburg. He had about 25,000 troops along with sixty-six pieces of artillery. A portion of General Ewell's Corps was seen in Smithsburg with at least sixteen pieces of artillery. He then reported that a small band of Confederate cavalry was located in Boonsboro, but soon moved on.

General Stahel's deployment was stretched all across South Mountain. He had one brigade and a section of artillery posted at Crampton's Gap as well as a brigade and two sections of artillery from General Howard's Corps. He had one regiment at Turner's Gap and one brigade and two sections of artillery at Middletown.

During the morning of June 27th, General David B. Birnery was ordered by General Reynolds to send one infantry brigade and a battery of rifle guns to Crampton's Gap to relieve the forces of General Howard once he arrived in the neighborhood of Jefferson and Burkittsville. While General Howard's men at Crampton's Gap were waiting to be relieved, Colonel William D. Mann commanding the 7th Michigan Cavalry occupied Turner's Gap and sent patrols throughout the Cumberland Valley toward Hagerstown. He reported that four hundred Confederate cavalry and three pieces of artillery were in the area of Jones' Crossroads. Most of the Confederate forces had left Hagerstown and were concentrating their efforts at Chambersburg. Some of Colonel Mann's scouts reported that large quantities of supplies were being sent back to Virginia. During the Invasion of Pennsylvania, the Confederate Army was gathering supplies and sending them from Chambersburg to Winchester, Virginia and the empty wagons would come back and be refilled again.

General Adolph Von Steinwehr commanding the 11th Corps' Second Division sent a dispatch to General John Reynolds who was at Middletown that his scouts had seen portions of Stuart's Cavalry pass through Williamsport during the afternoon. This may be part of the cavalry force that was foraging the farms of Pennsylvania and returning the goods to Winchester. These foraging excursions happened throughout the Pennsylvania Campaign. In preparation of any Confederate advance toward Frederick, General Steinwehr deployed his force at Turner's Gap. Colonel Charles R. Coster's Brigade was deployed near Turner's Gap; Colonel Orland Smith's Second Brigade occupied the summit of Turner's Gap with one regiment connecting to Colonel Coster's First Brigade. The artillery was left with the Colonel Coster's First Brigade and if necessary were to be brought up in a half hours time. He also had outposts scattered all over South Mountain. Washington Monument was used because of the view of the valley below.

During the afternoon, General Oliver O. Howard occupied Turner's Gap and sat up his headquarters at the Mountain House. General Howard also reported that he saw no threat of the Confederate Army in or around Boonsboro or the Valley. Colonel Smith had Captain Buchwalter of the 73rd Ohio Infantry operate the signal station at Washington Monument. Captain Buchwalter noted that one can clearly distinguish the roads leading from Boonsboro to Hagerstown, Sharpsburg, and Shepherdstown, and did not see any troops moving upon them, except the Union cavalry.

Lt. Colonel Asmusse who served as the 11th Corps Chief of Staff reported that Confederate cavalry was driving cattle and horses through the valley toward Williamsport. He also noted that pickets were set in the fields outside of Hagerstown, Maryland. The headquarters of the Army of the Potomac moved to Frederick, and an attempt was made to open communication between Frederick and the station on Sugar Loaf Mountain, which proved unsuccessful due to the unfavorable condition of the atmosphere. A station of observation was established at Middletown, and communication opened from there to another point of observation at South Mountain Pass, and the results were reported to Generals John F. Reynolds and Oliver O. Howard.

During the Pennsylvania Campaign, all four companies of Cole’s Cavalry Battalion were detached and each company was to act as an independent organization. On June 27th, Lieutenant William A. Horner asked permission to take a dozen men and go through the Confederate lines for reconnaissance. After some debate Captain Albert Hunter, commanding Company C of Cole's Cavalry allowed a dozen of his troopers to go on scout. Lieutenant Horner’s detachment came out at Boonsboro and traveled to Waynesboro crossing over South Mountain at Monterey Pass and riding horseback to Fountain Dale.

Pegram's Artillery reached Maryland late in the evening on June 25th, crossing the Potomac River at Boteler's Ford. From there they traveled the roads that led into Hagerstown. Private John C. Goolsby who was a member of Crenshaw's Artillery recorded "We had the pleasure of seeing numerous Confederate flags displayed, which the boys greeted with loud bursts of applause. After camping awhile near the town, we broke camp and soon struck the Little Antietam stream, crossed it, and were soon in the land of milk and applebutter--Pennsylvania. What a sight greeted our eyes! This is a beautiful country, and we reached it at a season of the year when the whole earth was wrapped in nature's best attire--the velvet green. The roads were fine."

The next day the artillerist would be in Pennsylvania. Private Goolsby continued: "We pushed on and soon struck the village of Waynesboro, where United States flags were displayed in great numbers, which, of course, we greeted pleasantly. Another day's journey brought us to the foot of Cash [South] Mountain, where we had several men captured. "

By the time that parts of Pegram's Artillery Battalion had encamped at Fayetteville they had lost several horses. Because of the concerned state the horses were in, Lieutenant John Hampden (Ham) Chamberlayne led a small detail soldiers from Purcell, Crenshaw, and Lecture’s Batteries and made their way through Franklin County into Adams County where they came to Fairfield.

From Fairfield, Lieutenant Chamberlayne's men traveled toward Monterey when they came across a small church at Fountain Dale on June 28th. A small Lutheran Church, located on Old Waynesboro Pike near present day Jacks Mountain Road is where the encounter of Fountain Dale took place. It was Sunday and church services were underway. Lieutenant Ham Chamberlayne saw about 20 horses tied to a post and decided that these horses were are exactly what his battery needed.

Lieutenant Chamberlayne opened the door of the church and rushed in with his pistol drawn and demanded that each person give up their horse and that they would be paid in full by means of a treaty between the Confederate States Government and the United States Government. No dispute was made and Lieutenant Chamberlayne then walked back outside and untied the horses.

As Lieutenant Chamberlayne's men started for their camp, a detachment of cavalry was spotted coming down Waynesboro Pike. This was a small squad of horsemen under the command of Lt. William A. Horner. Seeing rebel horsemen near the church Lt. Horner, order his squad to halt near a brick school house near the Lutheran Church and try to intercept them.

It was at this time that Lieutenant Ham Chamberlayne hand-selected 6 men who had revolvers to turn and make a stand with him, while the others made their escape. Lieutenant Chamberlayne led his men directly toward Horner’s men and charged. A clash erupted between these two forces and Chamberlayne and his six men were taken prisoner. After the skirmish, Horner's Keystone Rangers retired with their prisoners to Emmitsburg. Only nine men of the detail made it safely back to Fayetteville. Sometime after the skirmish, local residents were encouraged to take inventory of their livestock and to report any missing animals to the local sheriff.

Read part 3: Skirmishes at Cashtown & Chambersburg