Concert-Room Acoustics 231 Science and Spiritualism 237 Mathematical Fictions 251 World-Smashing 257 The Dying Trees in Kensington Gardens 261 The Oleaginous Products of Thames Mud: Where they Come from and Where they Go 266 Luminous Paint 269 The Origin and Probable Duration of Petroleum 273 The Origin of Soap 281 Oiling the Waves 285 On the so-called “Crater Necks” and “Volcanic Bombs” of Ireland 290 Travertine 296 The Action of Frost in Water-Pipes and on Building Materials 300 The Corrosion of Building Stones 308 Fire-Clay and Anthracite 312 Count Rumford’s Cooking-Stoves 320 The “Consumption of Smoke” 327 The Air of Stove-Heated Rooms 332 Ventilation by Open Fireplaces 337 Domestic Ventilation 341 Home Gardens for Smoky Towns 351 Solids, Liquids, and Gases 367 Murchison and Babbage 386 Atmosphere _versus_ Ether 389 A Neglected Disinfectant 392 Another Disinfectant 393 Ensilage 394 The Fracture of Comets 396 The Origin of Comets 398 SCIENCE IN SHORT CHAPTERS. THE FUEL OF THE SUN. I offer the following sketch of the main argument which is worked out more fully in the essay I published in January, 1870, under the above title, hoping that many who hesitate to plunge into a presumptuous speculative work of more than 200 octavo pages may read this article, and reflect upon the subject.