Alexander : a history of the origin and growth of the art of war from ...

312 DARIUS' LEFT BROKEN.ite method, — an oblique order of battle, tbe left refused. Itwas again accidental, but none the less effective. It enabledhim to force the attack on the Persian left centre, which hesaw was the weak point of Darius' line.The impact of the Companions and hyj^aspists was tremendous.There was but a brief resistance. No soldiers underDarius' standard could stand up under the blow. The Persianline reeled and weakened. The Macedonians pressedsteadily on. So soon as Alexander had driven back that partof the Persian left wing which he had struck, he found himselfon the left flank of the Greek mercenaries in the Persiancentre, on whom Darius peculiarly relied, and who had so farheld the Macedonian phalanx in check. Where Alexanderled, fortune always followed. He had won a foothold of firstimportance. Success here made it certain that success byDarius' right could not be fatal ; for Alexander cut Dariusfrom his line of retreat by turning his left or strategic flank.The discovery that the enemy has a strategic flank, that is,a flank the turning of which will cut him off from his line ofretreat, has often been ascribed to Napoleon, and it is no doubttrue that no captain ever made use of this weak point on sogrand a scale or so efficiently as the great Corsican. Buthere it is plain that Alexander saw the advantage of an attackon this flank ; we shall see him make use of the idea again ;and that Hannibal very clearly understood the matter isshown by the march through the Arnus marshes. It was thecommentators of Napoleon's campaigns who explained to theworld the value of that captain's methods. Napoleon himselfrepeatedly acknowledges his indebtedness to his predecessorsin the art. But he carried what they taught him to its highestdegree of perfection.In the centre the Macedonian phalanx had not been sospeedy or so successful as it had on the right where Alexan-