James Ford Rhodes (18481927). History of the Civil War, 18611865 1917.
Maryland, received orders on June 22, permitting him to move forward. If Harrisburg comes within your means, wrote Lee, capture it. Advancing into Pennsylvania and halting one day at Chambersburg to secure supplies, Ewell reached Carlisle on June 27 and sent Early with one division to seize York. On the formal surrender of the town by the chief burgess and a deputation of citizens, Early laid it under contribution, receiving 1000 hats, 1200 pairs of shoes, 1000 socks, three days rations of all kinds and $28,600 United States money. Having already burned the railroad bridges on the way to York, he now sent an expedition to take possession of the Columbia bridge over the Susquehanna, a wooden structure on stone pillars, one mile and a quarter long and bearing the railroad, a wagon-road and a tow-path for the canal. He intended to march his division across this bridge, cut the line of the Pennsylvania railroad, take Lancaster, lay it under contribution and attack Harrisburg in the rear while the remainder of Ewells corps assailed it from the front. But a regiment of Pennsylvania militia, in fleeing before the Confederates, set fire to the bridge and Earlys men found it impossible to arrest the flames.
Ewell, meanwhile, through requisitions and search of shops, had secured ordnance, medical and other valuable stores; had collected near 3000 head of cattle and located 5000 barrels of flour. In the course of a reconnaissance his cavalry, supported by a section of artillery, approached to within three miles of Harrisburg and engaged the pickets of the militia forces assembled under General Couch for its defence. By June 29, he had everything ready and purposed moving on Harrisburg. Two days earlier Longstreet and Hill had reached Chambersburg and Lee was there in command. His whole army numbering 75,000 was on Pennsylvania soil.