Theories and Definitions.--Franklin’s and a Modern One.-- Varieties of the Force.--Generation.--Dynamic Energy.-- Discoveries before the Nineteenth Century.--Magnetism and Electricity.--Fathers of the Science.--Doctor Gilbert.--Otto von Guericke.--Sir Isaac Newton.--Gray.--Dufay.--Professor Muschenbroeck.--Cuneus.--Charles Morrison.--Franklin and Galvani.--Volta.--The Door to Nineteenth Century Inventions then Opened.--Fabroni.--Sir Humphry Davy, Wollaston, Nicholson, and Carlisle.--Ritter Followed--Electrolysis.--Faraday and its Laws.--Davy and the Electric Light.--Batteries.--Daniell.-- Grove.--Bunsen.--Brilliant Discoveries from 1800 to 1820.-- Oersted, Schweigger.--Magnetising Helix.--Indicators.--Arago and Davy.--Ampère’s Discoveries.--Sturgeon and the first Electro-Magnet, 1825.--Telegraphy.--Gauss, Weber, Schilling.-- Professor Barlow’s Demonstration that Telegraphy was Impracticable.--Joseph Henry.--Powerful Magnets.--Modern and Ancient Telegraphy of Various Kinds.--The Third Decade.--George Simon Ohm.--Steinheil.--Telegraph of Morse, Vail, Dana, Gale.-- Wheatstone.--U.S. Supreme Court on Morse System.--His Alphabet and Submarine Telegraph.--Michael Faraday and Science of Magnets.--Steam and Magneto-Dynamo Machines.--Chemical Affinity and Electricity.--Helmholtz, Faraday, Henry, and Pixii.-- Ruhmkorff Coil.--Page.--Electrical Light.--Decomposition of Water.--Professor Nollet.--First Practical Electric Light Shone on the Sea, 1858.--Faraday and Holmes.--Lighthouse Illumination.--Dr. W. Siemens.--Wilde’s Machine.--Other Powerful Magnetic Machines.--Field Magnets.--Z. Gramme.-- The Various Ways and Means of Developing Electric Light.-- Geissler Tubes.--First House Lighted in America.--Moses G. Farmer.--Jablochoff’s Candle.--French Regulators.--Outdoor and Indoor Illumination.--Siemens, Farmer, Brush, Maxim, Westinghouse, Edison, Swan, Lane--Fox and Others.--Arc Lamps of Heffner von Alteneck.--Ocean Cables.--Cyrus W. Field.--John Bright’s Expression.--Weak Currents.--Thomson’s Remedy.--Mirror Galvanometer.--Centennial Exhibition and the Telephone.-- Alexander Graham Bell, 1875.--The Telephone and Helmholtz’ Theory of Tone.--Scott’s Phonautograph.--Page’s Production of Galvanic Music and Researches of Reis.--Its Slow Growth.--The Ideas of Faraday and Henry still the Basis of the Great Machines.--“Lines of Force.”--Electric Railway.--Storage Batteries.--Dynamos.--First Railway at Berlin, 1879.--Then Saxony, Paris, London, New York.--Telpherage by Professor Jenkin.--Problems Solved.--Electrical Magicians.--Edison and Tesla.--Recent Improvements in Telegraphy.--The Talks Both Ways at Same Time and Multiplied.--Printing Systems by Types and Otherwise.--Electrical Elevators.--Microphone.--Ticks of a Watch and the Tread of a Fly Recorded.--Musical Sounds from Minerals and Other Substances.--Signalling and Other Appliances.--The X Rays.--Wireless Telegraphy. 111 CHAPTER X.