Mediæval cosmology and geography await a thorough student; they are imbedded in the wastes of theological discussions of the Fathers, or hidden in manuscript cosmographies in libraries of Europe. It should be noted that confusion has arisen from the use of the word _rotundus_ to express both the sphericity of the earth and the circularity of the known lands, and from the use of _terra_, or _orbis terrae_, to denote the inhabited lands, as well as the globe. It has been pointed out by Ruge (_Gesch. d. Zeitalters der Entdeckungen_, p. 97) that the later Middle Age adopted the circular form of the _oekoumene_ in consequence of a peculiar theory as to the relation of the land and water masses of the earth, which were conceived as two intercepting spheres. The _oekoumene_ might easily be spoken of as a round disk without implying that the whole earth was plane.[351] That the struggle of the Christian faith, at first for existence and then for the proper harvesting of the fruits of victory, induced its earlier defenders to wage war against the learning as well as the religion of the pagans; that Christians were inclined to think time taken from the contemplation of the true faith worse than wasted when given to investigations into natural phenomena, which might better be accepted for what they professed to be; and that they often found in Scripture a welcome support for the evidence of the senses,—cannot be denied. It was inevitable that St. Chrysostom, Lactantius, Orosius and Origines rejected or declined to teach the sphericity of the earth. The curious systems of Cosmas and Aethicus, marked by a return to the crudest conceptions of the universe, found some favor in Europe. But the truth was not forgotten. The astronomical poems of Aratus, Hyginus, and Manilius were still read. Solinus and other plunderers of Pliny were popular, and kept alive the ancient knowledge. The sphericity of the earth was not denied by St. Augustine; it was maintained by Martianus Capella, and assumed by Isidor of Seville. Bede[352] taught the whole system of ancient geography; and but little later, Virgilius, bishop of Saltzburg, was threatened with papal displeasure, not for teaching the sphericity of the earth, but for upholding the existence of antipodes.[353] The canons of Ptolemy were cited in the eleventh century by Hermann Contractus in his _De utilitatibus astrolabii_, and in the twelfth by Hugues de Saint Victor in his _Eruditio didascalica_. Strabo was not known before Pope Nicholas V., who ordered the first translation. Not many to-day can illustrate the truth more clearly than the author of _L’Image du Monde_, an anonymous poem of the thirteenth century. If two men, he says, were to start at the same time from a given point and go, the one east, the other west,— Si que andui egaumont alassent Il convendroit qu’il s’encontrassent Dessus le leu dont il se mûrent.[354]