Such was the fortress built against human science in the sixth century, by Cosmas; and it stood. The innovators attacked it in vain. The greatest minds in the Church devoted themselves to buttressing it with new texts, and throwing out new outworks of theologic reasoning. It stood firm for two hundred years, when a bishop--Virgilius of Salzburg--asserts his belief in the existence of the antipodes. It happened that there then stood in Germany, in the first years of the eighth century, one of the greatest and noblest of men--St. Boniface. His learning was of the best then known; in labors he was a worthy successor to the apostles; his genius for Christian work made him, unwillingly, Primate of Germany; his devotion afterward led him, willingly, to martyrdom. There sat, too, at that time, on the papal throne, a great Christian statesman--Pope Zachary. Boniface immediately declares against the revival of such a terrible heresy as the existence of the antipodes. He declares that it amounts to the declaration that there are men on the earth beyond the reach of the means of salvation; he attacks Virgilius; he calls on Zachary for aid; effective measures are taken, and we hear no more of Virgilius or his doctrine. Six hundred years pass away, and in the fourteenth century two men publicly assert the doctrine. The first of these, Peter of Abano, escapes punishment by natural death; the second, known as Cecco d'Ascoli, a man of seventy years, is burned alive. Nor was that all the punishment: that great painter, Orcagna, whose terrible works you may see on the walls of the Campo Santa at Pisa, immortalized Cecco by representing him in the flames of hell.[13] Still the idea lived and moved, and a hundred years later we find the theologian Tostatus protesting against the doctrine of the antipodes as "unsafe." He has invented a new missile--the following syllogism: "The apostles were commanded to go into all the world, and to preach the gospel to every creature; they did not go to any such part of the world as the antipodes, they did not preach to any creatures there: _ergo_, no antipodes exist." This is just before the time of Columbus.