The Ancient Volcanoes of Great Britain, Volume 1 (of 2)Note 142 — Chapter XII · CHARACTERS OF THE SILURIAN SYSTEM IN BRITAIN. THE ARENIG VOLCANOESReading editionAfter Messrs. Cole and Holland, Geol. Mag. (1890), p. 450.◇Copy noteReturn to CHAPTER XII CHARACTERS OF THE SILURIAN SYSTEM IN BRITAIN. THE ARENIG VOLCANOES