...it was not till the 24th that the main body of his army entered Maryland. Instead of crossing the Potomac, as he had intended, east of the Blue Ridge, he was compelled to do it at Sheppardstown and Williamsport , thus materially deranging his entire plan of campaign north of the river. Stuart, who had been sent with his cavalry to the east of the Blue Ridge to guard the passes of the mountains, to mask the...