By Dr. JOHN SCOTT KELTIE, F.R.G.S., F.S.S., F.S.A., Hon. Mem. Geographical Societies of Paris, Berlin, Rome, Brussels, Amsterdam, Geneva, etc.; author of _Report on Geographical Education_, _Applied Geography_. │The History of Geology.│ By HORACE B. WOODWARD, F.R.S., F.G.S., Assistant Director of Geological Survey of England and Wales; author of _The Geology of England and Wales_, etc. │The History of Anthropology.│ By A. C. HADDON, M.A., Sc.D., F.R.S., Lecturer in Ethnology, Cambridge and London; author of _Study of Man_, _Magic and Fetishism_, etc. │The History of Old Testament Criticism.│ By ARCHIBALD DUFF, Professor of Hebrew and Old Testament Theology in the United College, Bradford; author of _Theology and Ethics of the Hebrews_, _Modern Old Testament Theology_, etc. │The History of New Testament Criticism.│ By F. C. CONYBEARE, M.A., late Fellow and Praelector of Univ. Coll., Oxford; Fellow of the British Academy; Doctor of Theology, _honoris causa_, of Giessen; Officer d’Academie; author of _Old Armenian Texts of Revelation_, etc. Further volumes are in plan on the following subjects: │Mathematics and Mechanics.│ │Molecular Physics, Heat, Life, and Electricity.│ │Human Physiology, Embryology, and Heredity.│ │Acoustics, Harmonics, and the Physiology of Hearing, together with Optics Chromatics, and Physiology of Seeing.│ │Psychology, Analytic, Comparative, and Experimental.│ │Sociology and Economics.│ │Ethics.│ │Comparative Philology.│ │Criticism, Historical Research, and Legends.│ │Comparative Mythology and the Science of Religions.│ │The Criticism of Ecclesiastical Institutions.│ │Culture, Moral and Intellectual, as Reflected in Imaginative Literature and in the Fine Arts.│ │Logic.│ │Philosophy.│ │Education.│ CONTENTS CHAPTER I PAGE STATE OF CHEMISTRY IN THE MIDDLE OF THE NINETEENTH CENTURY 1 Introductory. Some Founders of Modern Chemistry: Liebig, Wöhler, Dumas. Rapid Extension of Organic Chemistry after 1850: Laurent and Gerhardt, Hofmann. Development of theory in Organic Chemistry. Other representative men of the middle period of the Nineteenth Century: Graham, Williamson, Bunsen. Modern Chemistry in relation to the Atomic Theory. CHAPTER II THE CHEMICAL ELEMENTS DISCOVERED SINCE 1850 26 Nomenclature and Classification of Elements. Numerical relationships. Modes of discovery. The Spectroscope. Cæsium, rubidium, thallium, indium, gallium, scandium, germanium. The rare earth elements. Industrial applications of rare elements. CHAPTER III