Michael Scot brought together information about the volcanoes of the Eolian (Lipari) Islands and of Sicily which he included in a discourse on natural phenomena that he prepared for his patron Frederick II.[1015] He speaks of “Strongulus” (Stromboli), “a mountain which is in the midst of the sea,” of “Strongulinus” (Strombolicchio), “Vulcanus” (Vulcano), “Vulcaninus” (Vulcanello?), “Moncibellus” (Etna), and the isle of Lipari, “on which there are all manner of fine trees and grains.” From the summit of Stromboli and “Strongulinus,” a lesser mountain than Stromboli, great fiery flames are continuously emitted. The other four, he declares, emit flames only when the south wind (_Auster_) blows; and, when the flames cease, a mighty smoke issues from them. The eruptions are often accompanied by showers of scorched rock and sometimes with roots of trees (? _sticiones lignorum_) and cinders; the ground is covered and the air obscured as stream waters are clouded with sand. Glowing bombs are hurled aloft like sparks from a furnace; when these fall to the ground they burst into fragments, great and small, and in these fragments is found the pumice which writers use. This pumice floats on the sea and is carried ashore, where the people collect it for building walls and for uses similar to those to which we put bricks. Liquid sulphur is also gathered by sailors from the surface of the sea thereabouts in baskets and bowls. The nearer this may be obtained to the mountains whence it boils forth, the better its quality. VOLCANOES OF ICELAND In the _Topographia Hiberniae_ of Giraldus Cambrensis we find a description of the volcanic eruptions of Iceland.[1016] After remarking that thunder and lightning are rare in the northern isle, he goes on to explain that there is another and even worse affliction than these; every year or two fire bursts out of a certain part of the island like a whirlwind with a violent gale and melts everything in its path; he adds that the cause of this phenomenon and whether it originated above or below ground are unknown. Into two manuscripts of Solinus, the oldest of which dates from the twelfth century, there was inserted some additional information about the northern isles. We are told that the marine ice on the coasts of Iceland “ignites itself on collision, and when it is ignited it burns like wood” (Nansen’s translation).[1017] Adam of Bremen had also spoken of ice that appeared to be black and dry on account of its age and burned when kindled.[1018] Though it has been suggested that this impression may have been derived from mists arising from the ice, the story was perhaps, as Nansen observes, “due to statements about volcanoes and boiling springs which have been confused with it. The black color and dryness of the ice may have been due to confusion with lava or with floating pumice stone in the sea.”[1019]