He described the island as having the form of an isosceles triangle, as may be seen upon the foregoing plan. Three promontories formed the three angles,--Belerium being now Land's End, Cantium Cape Pepperness, and Orcas Duncansby Head. He found the inhabitants of the southern coast industrious and sociable, peaceable, honest, and sober. They raised wheat and worked rich mines of tin. As he sailed northward, along the eastern coast, he noticed that the days grew sensibly longer; and at Point Orcas, nineteen hours elapsed between the rising and the setting of the sun. He sailed still northward, and six days after leaving Orcas he came to an island, or a continent--he knew not which,--which he called Thule. As he found he could go no farther to the north, he spoke of this spot as _Ultima Thule_, an expression which has passed into the figurative language of all modern nations as one denoting any remote point. Thule is generally considered to have been Shetland, although theories have been ardently advocated making it respectively Iceland, Sweden, and Jutland. The narrative of Pytheas, which has been thus far clear and reliable, assumes at this point a very fabulous aspect. He declares that north of Thule there was neither earth, nor sea, nor air. A sort of dense concretion of all the elements occupied space and enveloped the world. He compared it to the thick, viscid animal substance called _pulmo marinus_, a sort of mollusk or medusa. He said that this substance was the basis of the universe, and that in it earth, air, and sky hung, as it were, suspended. This illusion has been explained by the dreary spectacle of fogs, mists, rains, and tempests which at this point of his voyage must have met the gaze of the daring navigator. It would have been difficult for any mind, in those early ages, to have been on its guard against the sinister impressions likely to result from the contemplation of a scene so appalling. It must be remembered that Pytheas was accustomed to the pure and transparent atmosphere, the dazzling sky, and the phosphorescent waters of the Mediterranean. It would have been astonishing if a man educated among the splendors of an almost tropical climate had not been oppressed by influences so gloomy. It was the belief of all early navigators that a point would be found somewhere without the Pillars of Hercules beyond which it would be impossible to penetrate. While timid adventurers declared they had arrived at this point hardly a week's sail from the Straits, and declared that an atmosphere of mist, darkness, and gigantic sea-weed barred their passage, Pytheas did not allow his imagination to be affected or his courage to be shaken till he found himself in presence of the sombre and formidable scenery of what, with true geographical propriety, he denominated "Thule and her utmost isles."