The geologist Sir Henry Thomas De la Beche (1796-1855) made important contributions as both a surveyor and a theorist. Elected to the Royal Society in 1823, he mapped geological strata in Devon during the 1830s and became the founding director of the British Geological Survey, the world's first national geological survey. In 1847, he was elected president of the Geological Society of London. Reflecting the scope of his scientific knowledge, the present work covers a wide range of topics, including the density of planets, the mineralisation of organic remains, and what could be inferred from the fossils thus created. The book was first published in 1834, the year he became embroiled in an argument with his contemporary Roderick Murchison. Lasting several years, the dispute became known as the 'The Great Devonian Controversy'. De la Beche's Geological Manual (third edition, 1833) has also been reissued in this series.