The river lock had a peculiar feature, which led to a great embarassment for Union General McClellan in February of 1862. As he sent General Banks' division across the light pontoon bridge that his engineers had finished just upstrem, McClellan was planning to set up a more permanent bridge for reinforcements and heavy equipment, using canal boats as pontoons. But when the canal boats arrived, the engineers discovered that the river lock was narrower than the standard locks on the C&O Canal, apparently because it was only intended to transfer boats from the Shenandoah, which were built to smaller dimensions. And as it turned out, the C&O boats were 6 inches too wide to make it through the river lock. While McClellan still had the pontoon bridge at his disposal, he was sufficiently disquieted to call off his plans to proceed south to Winchester.

Lincoln was furious at the delay, perhaps because he suspected that McClellan was using it as an excuse for halting his forces, but he fixed his anger on the failure to check the dimensions of the canal lock. Since McClellan was not nearby, the President instead upbraided his father-in-law: "Why in the Nation, General Marcy, couldn't the General have known whether a boat would go through that lock before spending a million dollars getting them there?" Wags in Washington summed up the situation by saying that the expedition had died of "lockjaw."

Mile 60.7:

Early in the Civil War, both Union and Confederate commanders recognized the importance of controlling the "Maryland Heights," that portion of Elk Ridge that looms over the canal and the town of Harpers Ferry. Abner Doubleday set about placing artillery here in the summer of 1861, and a military road was constructed up the face of the mountain. General Banks believed that "two or three pieces of heavy artillery will command the town and sweep roads measurably all the roads leading to it, as the turnpike to Charlestown, the road leading to Leesburg, and the mountain road from Keys' Ferry to Loudoun Heights, and to Harper's Ferry across the Shenandoah."

When Colonel Dixon S. Miles rushed to the town of Harper's Ferry in September 1862 to command its defense, he was well aware of the importance of the Heights, and ordered that it be defended at all costs. However, shortly after the Confederates began their assault, Dixon ordered a withdrawal, with the predictable consequence that the garrison in Harpers Ferry was soon shelled into surrender. The quick surrender made it possible for Stonewall Jackson to reinforce Robert E. Lee just in time to stave off disaster at Antietam.

Colonel Miles was one of the casualties, which spared him the fate of several of his fellow officers who were arrested two weeks later and brought before a military commission that had been assembled in Washington to investigate this "unfortunate affair." The commission collected a good deal of material that cast suspicion upon Miles' judgment and even his loyalty, and concluded that the "strangely unanimous testimony" demonstrated an "incapacity, amounting almost to imbecility."

General Walker's account of the bombardment of Harper's Ferry:

About an hour after my batteries opened fire, those of A.P. Hill and Lawton followed suit, and near three o'clock those of McLaws. But the range from Maryland Heights being too great, the fire of McLaws's guns was ineffective, the shells bursting in mid-air, without reaching the enemy. From my position on Loudoun Heights my guns had a plunging fire on the Federal batteries, a thousand feet below, and did great execution. By five o'clock our combined fire had silenced all the opposing batteries, except one of two guns east of Bolivar Heights, which kept up a plucky but feeble fire, until night put a stop to the combat.

During the night of the 14th-15th, Major (afterwards brigadier-general of artillery) R. Lindsay Walker, chief of artillery of A.P. Hill's division, succeeded in crossing the Shenandoah with several batteries, and placing them in such a position, on the slope of Loudoun Mountain far below me, as to command the enemies works. McLaws got his batteries into position nearer the enemy, and at daylight of the 15th the batteries of our five divisions were pouring their fire on the doomed garrison. The fire of my batteries, however, was at random, as the enemy's position was entirely concealed by a dense fog, clinging to the sides of the mountain, far below. But my artillerists trained their guns by the previous day's experience and delivered their fire through the fog.

The Federal batteries promptly replied, and for more than an hour maintained a spirited fire; but after that time it grew more and more feeble, until about eight o'clock, when it ceased altogether, and the garrison surrendered. Owing to the fog I was ignorant of what had taken place, but surmising it, I soon ordered my batteries to cease firing. Those of Lawton, however, continued someminutes later. This happened, unfortunately, as Colonel Dixon S. Miles, the Federal commander, was at this time mortally wounded by a fragment of shell while waving a white flag in token of surrender.

Sources:

• George B. McClellan, The Young Napoleon, Stephen W. Sears, Ticknor & Fields, New York, 1988, reprinted by Da Capo Press, New York, 1999. [See discussion of the problem with the river lock on pages 156-158]
• Six Years of Hell, Harpers Ferry During the Civil War, Chester G. Hearn, Louisiana State University Press, Baton Rouge, Louisiana, 1996.
• My Life in the Old Army, The Reminiscences of Abner Doubleday, edited by Joseph E. Chance, Texas Christian University Press, Ft. Worth, Texas, 1998.
• War of the Rebellion, A Compilation of the Official Records of the Union and Confederate Armies, Series 1, Volume 19. [See Part 1, pages 550-803, for records of the Military Commission on Harpers Ferry.].
• "Harper's Ferry and Sharpsburg," by (General) John G. Walker, in The Century Magazine, vol. 32, issue 2, June 1886, pp. 296-309. [Viewable on-line as a part of Cornell University's Making of America collection.]