JAMES CROLL. EDINBURGH, _March, 1875_. CONTENTS. CHAPTER I. INTRODUCTION. PAGE The Fundamental Problem of Geology.—Geology a Dynamical Science.—The Nature of a Geological Principle.—Theories of Geological Climate.—Geological Climate dependent on Astronomical Causes.—An Important Consideration overlooked.—Abstract of the Line of Argument pursued in the Volume 1 CHAPTER II. OCEAN-CURRENTS IN RELATION TO THE DISTRIBUTION OF HEAT OVER THE GLOBE. The absolute Heating-power of Ocean-currents.—Volume of the Gulf-stream.—Absolute Amount of Heat conveyed by it.—Greater Portion of Moisture in Inter-tropical Regions falls as Rain in those Regions.—Land along the Equator tends to lower the Temperature of the Globe.—Influence of Gulf-stream on Climate of Europe.—Temperature of Space.—Radiation of a Particle.—Professor Dove on Normal Temperature.—Temperature of Equator and Poles in the Absence of Ocean-currents.—Temperature of London, how much due to Ocean-currents 23 CHAPTER III. OCEAN-CURRENTS IN RELATION TO THE DISTRIBUTION OF HEAT OVER THE GLOBE.—(_Continued._) Influence of the Gulf-stream on the Climate of the Arctic Regions.—Absolute Amount of Heat received by the Arctic Regions from the Sun.—Influence of Ocean-currents shown by another Method.—Temperature of a Globe all Water or all Land according to Professor J. D. Forbes.—An important Consideration overlooked.—Without Ocean-currents the Globe would not be habitable.—Conclusions not affected by Imperfection of Data 45 CHAPTER IV. OUTLINE OE THE PHYSICAL AGENCIES WHICH LEAD TO SECULAR CHANGES OF CLIMATE.