Horace Greeley, The American Conflict: A History of the Great Rebellion in the United States of America, 1860-65: its Causes, Incidents, and Results: Intended to exhibit especially its moral and political phases with the drift and progress of American opinion respecting human slavery from 1776 to the close of the War for the Union. Volume II.

[203] that the Rebel army had crossed into Maryland, is one of those puzzles so frequently exhibited in the strategy of that Generalissimo, which must find their solution in some higher, subtler, and more leisurely existence.

Gen. McClellan, at 3 A. M. of the 15th, was aware — for he telegraphed to Halleck — that he had been fighting the forces of D. H. Hill and Longstreet; that they had disappeared from his front; and that Franklin had likewise been completely successful at Crampton's Gap, on his left. He says in this dispatch: “The enemy disappeared during the night; our troops are now advancing in pursuit.” At 8 A. M., he telegraphed again — still from Bolivar, at the foot of Turner's Gap:

I have just learned from Gen. Hooker, in the advance — who states that the information is perfectly reliable — that the enemy is making for the river in a perfect panic; and Gen. Lee last night stated publicly that he must admit they had been shockingly whipped. I am hurrying every thing forward to endeavor to press their retreat to the utmost.

Had even the last sentence of this dispatch been literally true, Lee's destruction was imminent and certain.

It was now too late to save Harper's Ferry — for it had this moment fallen — but not too late to superbly avenge it. With Lee's order in his hand, McClellan must have known that the forces from which he and Franklin had just wrested the passes of the South Mountain were all that Lee had to depend upon, save those which he had detached and sent — mainly by long circuits — to reduce Harper's Ferry, and which must now be mainly on the other side of the Potomac. Precious hours had been lost by massing on his right instead of his left, and fighting for Turner's Gap, when he should only by a feint have kept as many Rebels there as possible, while he poured the great body of his army, in overwhelming strength and with the utmost celerity, through Crampton's Gap, crushing McLaws and relieving Harper's Ferry. But there was still time, if not to retrieve the error, at least to amend it. Our soldiers, flushed with unwonted victory, and full in the faith that they had just wrested two strong mountain-passes from the entire Rebel army, were ready for any effort, any peril. To press forward with the utmost rapidity, and so relieve Harper's Ferry, if that might still be, but at all events to crush that portion of the Rebel army still north of the Potomac, if it should stand at bay, and rout and shatter it should it attempt to ford the river; at the very worst, to interpose between it and the other half, under Jackson and Walker, should it attempt to escape westward by Hagerstown and Williamsport, and thus be in position to assail and overwhelm either half before it could unite with the other, was the course which seems to have been as obvious to McClellan as it must be to every one else.

The advance was again led by Gen. Pleasanton's cavalry, who overtook at Boonsborough the Rebel cavalry rear-guard, charged it with spirit, and routed it, capturing 250 prisoners and 2 gains. Richardson's division, of Sumner's corps, followed; pressing eagerly on that afternoon;¹ and, after a march of 10 or 12 miles,