By June 27th General Ewell’s Cumberland column had reached Carlisle, Pennsylvania. Ewell’s objective then was to sever the main line of the Pennsylvania Railroad and capture the state capital at Harrisburg. One of General Early’s brigades had already reached the Susquehanna River and Early was preparing to move against Harrisburg from the south. Meanwhile, however, Lee had learned that the Army of the Potomac had crossed the Potomac, and called an abrupt halt to the Second Corp’s advance. Ewell’s disappointment did not show in his report:
From [Carlisle] I sent forward my engineer, Captain [H. B.] Richardson, with General Jenkins's cavalry, to reconnoitre the defenses of Harrisburg, and was starting on the 29th for that place when ordered by the general commanding to join the main body of the army at Cashtown, near Gettysburg.Thus, Henry found himself on the outskirts of Harrisburg, Pennsylvania on June 29th, along with two other officers from Ewell’s staff. Two weeks earlier Union volunteers had begun to throw up earthworks on high ground opposite the city on the western bank of the Susquehanna. By the time Henry arrived, the new Union fortifications, baptized Fort Washington, were largely completed, and manned by 12,000 ill-trained militia men.
Henry and his companions probably found Jenkins at Peace Church near Mechanicsville. Jenkins had already sent out scouting parties on both sides of the main roads and when he described the lay of the land to Henry, it became clear that the best viewpoint over the fortifications was from Slate Hill, just southwest of Harrisburg. Jenkins detailed a company of his cavalry to accompany Henry and his companions for more detailed reconnaissance. In order that they might not be disturbed by Union patrols along the way, Jenkins’s main force began a diversionary artillery barrage against Union picket lines which had been sent out from Fort Washington. The barrage lasted a good two hours, which was sufficient for Henry and his companions to complete their reconnaissance.
|The view from Slate Hill 150 years later: the site of Fort Washington on the high ground to the left of Harrisburg|
Henry’s two companions returned to Carlisle that evening, and reported to Ewell that Union forces around Harrisburg were scarcely prepared to meet a Confederate attack. But it was already too late. Lee’s orders arrived about the same time as the reconnaissance report, and Ewell immediately began the movement southward.
It is not certain, however, that Henry Richardson returned to Carlisle on June 29th in time to leave with Ewell. Jed Hotchkiss, who shared a mess with Henry, wrote in his diary, for June 29th:
Captain Johnson and Major Clark came up last night and went with Richardson down to near Harrisburg, today, to reconnoiter. Johnson and Clark came back and spent the night with me.Hotchkiss didn't say whether or not Henry returned with Johnson and Clark, although he should have known, since they were all quartered in Carlisle Barracks. Perhaps, thinking that Hotchkiss's spaces would be too crowded to sleep four officers, Henry found a bunk elsewhere. On the other hand, if Henry stayed with Jenkins near Mechanicsville, he did not return to Carlisle until June 30. There, Jenkins found that Ewell had already left with Rodes's Division, moving about 31 miles south to Heidlersburg, where they camped for the night. Jenkins followed them as far as Petersburg (now York Springs), which they reached about 2:00 A.M. on July 1st. Jenkins's Brigade did not rejoin Ewell's Corps until late in the afternoon of July 1st at Gettysburg.
Whether or not Henry Richardson spent the night at Petersburg, he was well aware that Ewell would need all his staff at hand to coordinate movements, and eventually to carry out reconnaissance. Therefore, if he was not already riding with Ewell, he probably rejoined his staff, five miles down the road at Heidlersburg early on the morning of July 1st, but certainly at Middletown (now Biglerville), which Rodes's Division had reached toward 10:00 A.M. that morning.
So it seems that Henry Richardson did not miss the first hours of the battle after all.