The rock sequences have been studied by many geologists in the 19th and 20th centuries. Perhaps one of the first was Roderick Murchison who travelled this way in the early 1830s in search of material for his book "The Silurian System". He notes the quarrying and even an attempt to find coal in the side of Cusop Hill near 'The Criggy' circa 1800 by a tenant of Sir George Cornewalle. The rocks hereabouts do have blackish colourings in places of very early plant life and even primitive fishes have been found but mostly as disarticulated remains. Fish scales, boney plates and scales are usually found in pellety gritty beds.