CONTENTS. Vll 



of Actinism Phenomena of the Daguerreotype Chemical 

 Change produced upon all Bodies Power of Matter to restore 

 its Condition Light protects from Chemical Change Pho- 

 tographs taken in Darkness Chemical Effects of Light on 

 organized Forms Chemical Effects of Solar Heat Influence 

 of Actinism on Electricity Eadiations in Darkness Moser's 

 Discoveries, &c. ...... 166 



CHAPTER IX. 



ELECTRICITY. 



Discovery of Electrical Force Diffused through all Matter 

 What is Electricity? Theories Frictional Electricity- 

 Conducting Power of Bodies Hypothesis of two Fluids 

 Electrical Images Galvanic Electricity "-Effects on Animals 

 Chemistry of Galvanic Battery Electricity of a Drop of 

 Water Electro-chemical Action Electrical Currents 

 Thermo-Electricity Animal Electricity Gymnotus Tor- 

 pedo Atmospheric Electricity Lightning Conductors 

 Earth's Magnetism due to Electrical Currents Influence on 

 Vitality Animal and Vegetable Development Terrestrial 

 Currents Electricity of Mineral Veins Electrotype In- 

 fluence of Heat, Light, and Actinism on Electrical Phenomena 193 

 CHAPTER X. 



MAGNETISM. 



Magnetic Iron Knowledge of, by the Ancients Artificial 

 Magnets Electro-Magnets Electro-Magnetism Magneto- 

 ElectricityTheories of Magnetism The Magnetic Power 

 of soft Iron and Steel Influence of Heat on Magnetism 

 Terrestrial Magnetism Declination of the Cprnpass-needle 

 Variation of the Earth's Magnetism Magnetic Poles 

 Hansteen's Speculations Monthly and Diurnal Variation 

 Dip and Intensity Thermo-Magnetism Aurora Borealis 

 Magnetic Storms Magnetic conditions of Matter Dia- 

 Magnetism, &c. . . . . . 235 



CHAPTER XI. 



CHEMICAL FORCES. 



Nature's Chemistry Changes produced by Chemical Combina- 

 tion Atomic Constitution of Bodies Laws of Combination 

 Combining Equivalents Elective Affinity Chemical De- 

 compositionCompound Character of Chemical Phenomena 

 Catalysis or action of Presence Transformation of Or- 

 ganic Bodies Organic Chemistry Constancy of Combining 

 Proportions The Law of Volumes, the Law of Substitu- 

 tions, Isomeric States, &c. . . . . ,270 



CHAPTER XII. 



CHEMICAL PHENOMENA. 



Water Its Constituents Oxygen Hydrogen Peroxide of Hy- 

 drogen Physical Property of Water Ice Sea Water- 

 Chlorine Muriatic Acid Iodine Bromine Compounds of 



