In another connection[812] he explains that the violent _mistral_ of the Rhone valley generates in this region men who are windy, empty-headed, inconsistent, and most unreliable in their promises. The supposedly mollifying influence of a warmer climate on the Lombards is hinted at by Otto of Freising.[813] Otto believed that these tribes gave up their ferocity on settling in Italy, where they adopted Italian customs, partly because they married Italian women but partly also because of the nature of the country and climate (_ex terris aerisve_). We have already seen how Giraldus Cambrensis stressed the healthy qualities of damp and humid Ireland in contrast with the disease-breeding Orient. Even the most delicate persons thrive in Ireland, he said, and though the Eastern air may endow men with keener wits and intelligence, the West gives them stronger bodies and a more martial spirit.[814] CLIMATE OF ROME If we may believe Otto of Freising[815] and Gunther of Pairis,[816] the climate of Rome was even more noxious and dangerous in the twelfth than in the nineteenth century. Otto tells us that Frederick Barbarossa’s army arrived in Rome in midsummer when the Dog Star was on high. It was a time when the ponds, caverns, and ruinous places around the city were exhaling poisonous vapors, and the air in the entire vicinity had become densely laden with pestilence and death. Gunther enlarges on this, giving a circumstantial, though probably fanciful, account of the effects of the terrible Roman summer on the German army, especially of the disease and malaria engendered by the climate and foul condition of the city.[817] CHAPTER VIII THE WATERS _THE WATERS ABOVE THE FIRMAMENT_ RATIONALISTIC BELIEFS “And God made the firmament and divided the waters which were under the firmament from the waters which were above the firmament” (Gen. i, 7).