Cuillin He partnered Louis Agassiz on his trip to Scotland in 1840 and although they subsequently argued, Forbes went on to publish other important papers on Alpine glaciers. In 1904 Alfred Harker published "The Tertiary Igneous Rocks of Skye", the first detailed scientific study of an extinct volcano. The Cuillin encompasses a wide range of habitats, changing with altitude. At the base there are conifer plantations, coastal woodlands and areas of heather moorland and rough grassland. The lower slopes are covered by various different types of bog, with grassland on the better-drained slopes that are found above 400 m. Higher up,
Rùm Torridonian sandstone and shales resting on Lewisian gneiss. Two of the Cuillin are classified as Corbetts: Askival and Ainshval, (Old Norse for "mountain of the ash trees" and "hill of the strongholds" respectively) and Rùm is the smallest Scottish island to have a summit above . Other hills include Hallival, Trollaval ('mountain of the trolls'), Barkeval, and Sgurr nan Gillean (Gaelic: "peak of the young men") in the Cuillin and Ard Nev, Orval, Sròn an t-Saighdeir and Bloodstone Hill in the west. It is likely that only the higher peaks remained above the Pleistocene ice sheets as nunataks. Hallival and