Part I. Containing Experiments on the Flow of Plastic Bodies, and Observations on the Phenomena of Lava Streams: 1. Plastic models; 2. Analogy of glaciers to lava streams James D. Forbes; Part II. An Attempt to Establish by Observation the Plasticity of Glacier Ice: 3. De Saussure's theory; 4. Modifications of De Saussure's theory; 5. Experiments at Chamouni on the plasticity of ice James D. Forbes; Part III: 6. On the motion of glaciers of the second order; 7. On the annual motion of glaciers, and on the influence of seasons; 8. Summary of the evidence adduced in favour of the theory James D. Forbes; Part IV. On the Physical Phenomena of Glaciers: 9. Observations on the Mer de Glace (1858) John Tyndall; 10. On the veined structure of glaciers, with observations upon white ice-seams, air-bubbles and dirt-bands, and remarks upon glacier theories (1859) John Tyndall; 11. On the structure and motion of glaciers (1857) John Tyndall and Thomas H. Huxley.