Introduction

Science advances by taking new and unexpected turnings, pioneers opening up pathways which later workers follow and explore. This book takes the reader along several such geological paths that have followed from observations and theories first printed in The Quarterly Journal of the Geological Society of London (since 1971, the Journal of the Geological Society ). Following the paths, one sees the history of geological thought during the nineteenth and twentieth centuries. To achieve this desired structure for the book, leading geologists were invited to present their personal views on significant topics that had been brought to the fore in earlier contributions to the Journal , to evaluate the evidence presented and to give their view of how these seminal papers affected our present understanding of geological processes, and further to hazard where future paths of investigation may lie. Bringing these together under one cover serves two purposes: first to celebrate 150 years of continuous publication of papers by the Geological Society of London: second, it makes a British review of the current 'battle lines' across many fields of geological research. Not only will the serious research investigator discover the several turning points which have governed the paths of his study, but the general reader also will discover the delights, the fortunes and machinations taken by many leading British geologists. Others will use the chapters to answer the question: 'Does historical contingency govern the paths of geological exploration, as it has been said to govern the evolution of living creatures?' most of