The scientific duel which was now to take place was likely to task the genius and to bring into full display the peculiar powers and defects of the two chieftains of Europe. Each might be considered to be still in the prime of life, but Alexander, who was turned of forty-five, was already broken in health, while the vigorous Henry was eight years younger, and of an iron constitution. Both had passed then lives in the field, but the king, from nature, education, and the force of circumstances, preferred pitched battles to scientific combinations, while the duke, having studied and practised his art in the great Spanish and Italian schools of warfare, was rather a profound strategist than a professional fighter, although capable of great promptness and intense personal energy when his judgment dictated a battle. Both were born with that invaluable gift which no human being can acquire, authority, and both were adored and willingly obeyed by their soldiers, so long as those soldiers were paid and fed. The prize now to be contended for was a high one. Alexander's complete success would tear from Henry's grasp the first city of Christendom, now sinking exhausted into his hands, and would place France in the power of the Holy League and at the feet of Philip. Another Ivry would shatter the confederacy, and carry the king in triumph to his capital and his ancestral throne. On the approach of the combined armies under Parma and Mayenne, the king had found himself most reluctantly compelled to suspend the siege of Paris. His army, which consisted of sixteen thousand foot and five thousand horse, was not sufficiently numerous to confront at the same time the relieving force and to continue the operations before the city. So long, however, as he held the towns and bridges on the great rivers, and especially those keys to the Seine and Marne, Corbeil and Lagny, he still controlled the life-blood of the capital, which indeed had almost ceased to flow. On the 31st August he advanced towards the enemy. Sir Edward Stafford, Queen Elizabeth's ambassador, arrived at St. Denis in the night of the 30th August. At a very early hour next morning he heard a shout under his window, and looking down beheld King Henry at the head of his troops, cheerfully calling out to his English friend as he passed his door. "Welcoming us after his familiar manner," said Stafford, "he desired us, in respect of the battle every hour expected, to come as his friends to see and help him, and not to treat of anything which afore, we meant, seeing the present state to require it, and the enemy so near that we might well have been interrupted in half-an-hour's talk, and necessity constrained the king to be in every corner, where for the most part we follow him."