This was a very strong position. On the left it was practically inaccessible. To try storming it in front would be a doubtful experiment, sure to result in terrible loss of life. The only weak point was the right, which could be taken in flank by a long circuitous march through the woods. Accordingly, on the morning of the 11th of September, the British right wing, under Knyphausen, began skirmishing and occupying Washington's attention at Chadd's Ford; while the left column, under the energetic Cornwallis, marched up the Lancaster road, crossed the forks of the Brandywine, and turned southward toward Birmingham church, with the intention of striking the rear of the American right wing. It was similar to the flanking movement which had been tried so successfully at the battle of Long Island, a year before. It was quite like the splendid movement of Stonewall Jackson at Chancellorsville, eighty-five years afterward. In Howe's time such flanking marches were eminently fashionable. It was in this way that the great Frederick had won some of his most astonishing victories. They were, nevertheless, then as always, dangerous expedients, as the stupendous overthrow of the Austro-Russian army at Austerlitz was by and by to show. There is always a serious chance that the tables may be turned. Such flanking movements are comparatively safe, however, when the attacking army greatly outnumbers the army attacked, as at the Brandywine. But in all cases the chief element in their success is secrecy; above all things, the party attacked must be kept in the dark.