CONTENTS. 



ELECTRICITY. 



TABLE PAGE 



49. The Dimensions of Units 38 



50. The C. G. S. System 38 



51. Magnetic Units 39 



Electrostatic Units 40 



Electromagnetic Units 40 



Ratio of the Electrostatic and Electromagnetic Units . 41 



Relation between the Units in each System 41 



Practical Units 42 



Practical Standards of Resistance 43 



The Heating Effects of Currents 44 



Electrolysis 44 



Specific Inductive Capacities 45 



Contact Differences of Potential 45 



Electromotive Force of Constant Batteries 46 



Electromotive Force of Common Batteries 46 



On the Specific Resistance of Substances 47 



Resistances of Metals and Alloys 48 



Resistances of Solutions 49 



Resistances of Telegraph Cables 49 



Resistances of Non-Metals 49 



Resistances of Insulators 50 



Thermoelectric Forces 51 



Thermoelectric Forces at different Temperatures ... 51 



Thermoelectric Piles 51 



Morse's Alphabet 52 



Intensity of Magnetisation 52 



Magnetic Elements at London 53 



Magnetic Elements at Towns in Great Britain ... 53 



Magnetic Elements at Greenwich 54 



Magnetic Elements at Places Abroad 55 



Rough data in Electricity 96 



