Before his time, the only artillery brought into the open field consisted of huge, heavy guns, slowly dragged along by twelve, sixteen, or twenty horses or oxen, which, once placed, could only remain in one position, even though the entire battle had shifted elsewhere. Gustavus was the first who introduced flying artillery, capable of being rapidly transferred from one part of the field to another. At a siege, this valiant Swedish king would in the same day “be at once generalissimo, chief engineer to lay out the lines, pioneer, spade in hand and in his shirt digging in the trenches, and leader of a storming party to dislodge the foe from some annoying outwork. If a party of the enemy’s cavalry were to be surprised in a night attack, he would himself undertake the surprise. He, indeed, carried this quite too far, obeying overmuch the instinct and impulses of his own courageous heart. And yet there was also a true humility in it all,—a feeling that no man ought to look at himself as indispensable. ‘God is immortal,’ he was wont to reply, when remonstrated with on this matter, and reminded of the fearful chasm, not to be filled by any other, which his death would assuredly leave.” Richelieu said of him, “The king of Sweden is a new sun which has just risen, young, but of vast renown. The ill-treated or banished princes of Germany in their misfortunes have turned their eyes towards him as the mariner does to the polar star.” Gustavus was admitted by the ablest statesmen of Europe to be the ablest general of his time. He was familiar with the military tactics of ancient and modern times, and he devised a more effective system of warfare than his predecessors had known. In answer to the question, Why did Gustavus Adolphus enter into the religious contests of Germany, and assume the commanding place he filled in that terrible struggle known as the “Thirty Years’ War”? an able writer gives thus briefly the reason:— “First, a deep and genuine sympathy with his co-religionists in Germany, and with their sufferings, joined to a conviction that he was called of God to assist them in this hour of their utmost need. “Secondly, a sense of the most real danger which threatened his own kingdom, if the entire liberties, political and religious, of northern Germany were trodden out, and the free cities of the German Ocean, Stralsund and the rest, falling into the hands of the emperor, became hostile outposts from which to assail him. He felt that he was only going to meet a war which, if he tarried at home, would sooner or later inevitably come to seek him there. “And, lastly, there was working in his mind, no doubt, a desire to give to Sweden a more forward place in the world, with a consciousness of mighty powers in himself, which craved a wider sphere for their exercise.”