Light; it Provides Means for Identifying Substances (Coloured Illustration)

24 The Moon 28 Mars 29     Drawings by Professor Percival Lowell.   The Moon, at Nine and Three Quarter Days 29 A Map of the Chief Plains and Craters of the Moon 32 A Diagram of a Stream of Meteors Showing the Earth Passing Through Them 32 Comet, September 29, 1908 33     Photo: Royal Observatory, Greenwich. Comet, October 3, 1908 33     Photo: Royal Observatory, Greenwich. Typical Spectra 36     Photo: Harvard College Observatory. A Nebular Region South of Zeta Orionis 37     Photo: Mount Wilson Observatory. Star Cluster in Hercules 37     Photo: Astrophysical Observatory, Victoria, British Columbia. The Great Nebula in Orion 40     Photo: Yerkes Observatory. Giant Spiral Nebula, March 23, 1914 41     Photo: Lick Observatory. A Spiral Nebula Seen Edge-on 44     Photo: Mount Wilson Observatory. 100-Inch Telescope, Mount Wilson 45     Photo: H. J. Shepstone. The Yerkes 40-Inch Refractor 48 The Double-Slide Plate-Holder on Yerkes 40-Inch Refracting Telescope 49     Photo: H. J. Shepstone. Modern Direct-Reading Spectroscope 49     By A. Hilger, Ltd. Charles Darwin 56     Photo: Rischgitz Collection. Lord Kelvin 56     Photo: Rischgitz Collection. A Giant Spiral Nebula 57     Photo: Lick Observatory. Meteorite Which Fell Near Scarborough and is now to be Seen in the Natural History Museum 57     Photo: Natural History Museum. A Limestone Canyon 60     Reproduced from the Smithsonian Report, 1915. Geological Tree of Animals 61 Diagram of Amœba 61 A Piece of a Reef-Building Coral, Built up by a Large Colony of Small Sea-Anemone-Like Polyps, Each of which Forms from the Salts of the Sea a Skeleton or Shell of Lime 64     From the Smithsonian Report, 1917. A Group of Chalk-Forming Animals, or Foraminifera, Each about the Size of a Very Small Pin's Head 65     Photo: J. J. Ward, F.E.S. A Common Foraminifer (Polystomella) Showing the Shell in the Centre and the Outflowing Network of Living Matter, Along which Granules are Continually Travelling, and by which Food Particles are Entangled and Drawn in 65     Reproduced by permission of the Natural History Museum (after Max Schultze). A Plant-Like Animal, or Zoophyte, Called Obelia 68     Photo: J. J. Ward, F.E.S. Trypanosoma Gambiense 69     Reproduced by permission of The Quart. Journ. Mic. Sci. Volvox 69 Proterospongia 69 Green Hydra 72     Photo: J. J. Ward, F.E.S. Diagram Illustrating the Beginning of Individual Life 72 Earthworm 72     Photo: J. J. Ward, F.E.S. Glass Model of a Sea-Anemone 72     Reproduced from the Smithsonian Report, 1917. This Drawing Shows the Evolution of the Brain from Fish to Man 73 Okapi and Giraffe (Coloured Illustration) 74 Diagram of a Simple Reflex Arc in a Backboneless Animal Like an Earthworm 76 The Yucca Moth 76     Photo: British Museum (Natural History). Inclined Plane of Animal Behaviour 76 Venus' Fly-Trap 77     Photo: J. J. Ward, F.E.S. A Spider Sunning Her Eggs 77     Reproduced by permission from The Wonders of Instinct by J. H. Fabre. The Hoatzin Inhabits British Guiana 82 Peripatus 83     Photograph, from the British Museum (Natural History), of a drawing by Mr. E. Wilson. Rock Kangaroo Carrying its Young in a Pouch 83     Photo: W. S. Berridge, F.Z.S. Professor Thomas Henry Huxley (1825-95) 86     Photo: Rischgitz. Baron Cuvier, 1769-1832 86 An Illustration Showing Various Methods of Flying and Swooping public@vhost@g@gutenberg@html@files@20417@[email protected]#image149" class="pginternal"