linguistic:translation, stylistic:tone, information:filtering
Geology

The earliest geological period of the Palaeozoic era, the Cambrian, takes its name from the Cambrian Mountains, where geologists first identified Cambrian remnants. In the mid-19th century, Roderick Murchison and Adam Sedgwick used their studies of Welsh geology to establish certain principles of stratigraphy and palaeontology. The next two periods of the Palaeozoic era, the Ordovician and Silurian, were named after ancient Celtic tribes from this area.