In former times, the study of language was rarely pursued in isolation, and many of the other intellectual concerns that used to be intertwined with language study have long been on the record of historians of linguistics. The present volume is the first to probe into an association of linguistics that has so far been neglected: that with the study of the earth. The relations between linguistics and geology were intimate and manifold as both sciences were emerging in the 18th and 19th century. Highlighted in the contributions to this volume are biographical and institutional contacts, the joint interest in origins and very early developments and in the proper methods of acquiring knowledge about these, common structural and evolutionary concepts, and analogous problems in the classification of domains as fuzzy as languages and rocks.