Jethro Tull's music contains moments of both hard crunchiness and delicate beauty, and each has its adherents. ELP's organ-blasting “Knife-Edge” and Uriah Heep's metallic beast “Walking in Your Shadow” show how prog rock's heavier acts have borrowed Tull's growling riffs and elaborate rhythms. In contrast, Steven Wilson's dreamy, acoustic-based “The Watchmaker” reflects the influence of their medieval folk melodies and flute on 21st-century prog.