CONTENTS. 



CHAPTER XXXIV. 



SCIENCE OF THE NINETEENTH CENTURY (CONTINUED). 



PACK 



Early Theories about Heat Count Rumford shows that Heat can 

 be produced by Friction He makes Water boil by boring a 

 Cannon Davy makes two pieces of Ice melt by Friction His 

 conclusion about Heat How Latent Heat' is explained on 

 the theory that Heat is a kind of Motion Dr. Mayer suggests 

 the Determination of the Mechanical Equivalent of Heat Dr. 

 Joule's Experiments on the conversion of Motion into Heat Dr. 

 Hirn's Experiments on the conversion of Heat into Motion Proof 

 of the Indestructibility of Force and Conservation of Energy . 329 



CHAPTER XXXV. 



SCIENCE OF THE NINETEENTH CENTURY ^CONTINUED). 



Oersted discovers the Effect of Electricity upon a Magnet Electro- 

 MagnetismExperiments by Ampere on Magnetic and Electric 

 Currents Ampere's Early Life Direction of the North Pole of 

 the Magnet depends on the course of the Electric Currents 

 Magnetic Currents set up between two Electric Wires Electro- 

 Magnets made by means of an Electric Current Arago magne- 

 tises a Steel Bar with an ordinary Electrical Machine Faraday 

 discovers the Rotatory Movement of Magnets and Electrified 

 Wires Produces an Electric Current by means of a Magnet 

 Seebeck discovers Thermo-Electricity, or the production of Elec- 

 tricity by Heat Schwabe discovers Periodicity of the Spots on 

 the Sun Sabine suggests a connection between Sun-spots and 

 Magnetic Currents This proved in 1859 by Observations of 

 Carrington and Hodgson Electric Telegraph Wheatstone 

 Cooke Steinheil Morse Bain 34.1 



CHAPTER XXXVI. 



SCIENCE OF THE NINETEENTH CENTURY (CONTINUED). 



Davy discovers that Nitrous Oxide produces Insensibility Laugh- 

 ing-gas Safety-lamp, 1815 Nicholson and Carlisle discover 

 Decomposition of Water, 1800 Davy discovers the effect of 

 Electricity upon Chemical Affinity Faraday's Discoveries in 



