TELEGRAPH

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TELEGRAPH TELEPHONE
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Outline

• Visual Telegraphy
• Electric Telegraphy
• Telegraph Lines
• Telephone

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Visual Telegraphy

• Claude Chappe (1763-1805)
• Built By Abraham Bruguet (1793)
• Clockmaker
• Could Have Been Built Earlier (100 Years)
• Lacked Telescope
• Stations Too Close
• First Stations
• Menilmontant
• Saint-Martin-du-Tertre (21 Miles Away
• First Line
• Paris to Lille

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Chappe Semaphore System

• Masonry Towers
• Wooden T
• Horizontal Beam (Regulator)
• Pivoted On Axis
• Jointed Arms (Indicator)
• Pivoted On Regulator Ends
• Cranks Ropes
• 196 Different Positions
• Chappe Code - 92 Positions
• Diplomatic Dictionary
• 92 Pages - First Signal
• 92 Words Per Page - Second Signal
• Second Dictionary - Phrases

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Chappe Semaphore System

• Slowed Development Of Electric Telegraph
• France
• Nothing New Technologically
• Increased Communication
• Calais To Paris
• 33 Posts, 58 Leagues, 3 Minutes
• Toulon To Paris
• 10 Posts, 200 Leagues, 20 Minutes
• Used Extensively In WW I
• Still Used - Aircraft Carriers

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Electric Telegraphy

• Electric Battery
• Electromagnetism
• First Electric Telegraphs
• Relays
• Alphabetical Devices
• First French Telegraphic Devices
• Printing Devices
• Morse System
• Telegraph Lines
• Machinery Electrical Industry

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Electric Battery

• Telegraph - Electric Current
• Continuous
• Permanent
• Voltaic Pile - Not Satisfactory
• Cesar Bequerel (1828)
• Two-Fluid Class
• J.F. Daniell (1836)
• Daniell Cell
• Reliable
• Contiuous

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Electromagnetism

• Conductor Traversed By Electric Current
• Magnetic Needle Moves
• Georges-Louis Lesage (1774)
• Dischages Of Static Electricity From Leydon Jar
• 24 Wires For Alphabet
• Underground - Conductors Insulated By Glass
• Ampere (1820)
• Deviation Of Magnetic Needle

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Electromagnetism (Continued)

• Baron Schilling (1832)
• Six Indicators Six Wires
• Black Side White Side
• Two Additional Wires
• Call Signs
• Return Current
• Carl-August von Steinheil
• Single Circuit (1827)
• Return Current Through Ground (1828)

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First Electric Telegraphs

• Euston Camden In London (1837)
• 40 Years After Chappe
• 1 Mile Long
• Sir William F. Cooke (1806-1879)
• Sir Charles Wheatstone (1802-1875)
• Five Needles Circuits With Six Wires
• Wheatstone Clarke (1842)
• Two Needle Instrument
• Alexander Bain (1843)
• Single Needle Instrument

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Five Needle Telegraph By W C

• Wheatstone Cooke (1837)
• Top
• Receiver
• Bottom
• Transmitter

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Local Circuit Of W C Telegraph

• Left - Relay
• Right - Calling Device

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Transmitting-Receiving Post

• Built By Wheatstone Clarke (1842)
• Two Needle Instrument
• Right
• Transmitters Connections
• Left
• General View

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First Electric Telegraphs

• Electromagnet (1820s)
• Ampere Arago
• Coarse Wires With Few Coils
• Inappropriate For Operation Over Long Distances
• Took 20 Years To Be Adopted In Telegraph
• Telegraphic Devices
• Alphabetical Telegraph
• Electric Telegraph With Chappe Signals
• Morse System

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Relays

• Wheatstone (1837)
• Electrochemical
• Close Circuit From A Distance
• U Shaped Tube
• Acidulated Water Mercury
• Current Causes Hydrogen To Be Liberated
• Pressure Cause Mercury To Close Circuit Of
  Sounding Device

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Relays

• Wheatstone (1839)
• Close Circuit From A Distance
• Needle In Center Of Frame
• Fork Shaped Contact At One End
• Current Caused Fork To Plunge Into Containers Of
  Mercury
• Closed Local Circuit

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Alphabetical Devices

• Wheatstone Cooke
• Clock Movement At Each Post
• Pointer Turned In Jerks
• Many Variations
• Replaced Needle Devices

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First French Telegraphic Devices

• Louis Breguet (1844)
• Same Concept As Wheatstone
• 2 Needles - Chappe System
• Escapement
• Right - Transmitter
• Left - Receiver

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First French Telegraphic Devices

• Keyboard Sender
• Gustave Froment (1845)
• Replaced Crank Sender Of Breguets

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Printing Devices

• Wheatstone
• Replaced Dial And Pointer On Alphabetical
• 24 Radiating Arms With Letter Engraved
• Hammer Presses On Recording Cylinder
• Separate Control Circuit
• John W. Brett (1805-1863)
• Modified Keyboard Idea Of Froment

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Printing Devices

• David E. Hughes (1831-1900)
• Best Idea
• Synchonized
• Transmitter
• Receiver

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Morse System

• Samuel F. B. Morse (1791-1872)
• Painter Turned Physicist Mechanic
• Modern Day da Vinci
• Numerous Biographies
• Electromagnet With An Armature Holding A Stylus
• Left Long Short Marks On Paper As It Unrolled
• Tried Ink Pencil
• Decided On Rod That Embossed Paper
• Lacked Experience In Making Electromagnets
• Studied Works Of Joseph Henry (1797-1878)
• First Electromagnet Was 2 High

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Morse System

• Simplicity
• Make Signal With A Simple Mechanical Device
• Similar Movements
• Transmitter
• Receiver
• Single Code With 2 Elements
• Short Long Signals
• Combinations Of 4 Signals
• Every Letter Of Alphabet
• 12 22 32 42 2 4 9 16 31
• Similarities Symmetry

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Morse System

• Manual Transmitter
• Right - Flexible Blade (First Model)
• Left - Jointed Lever Type With Reversing Spring

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Morse System

• Perfected Morse System (1845)
• Diagram Of Connections
• Baltimore To Washington (1845)
• Adopted Throughout Europe (Beginning 1846)
• International Communication (1854)

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Telegraph Lines

• Success Of Telegraph Depended On
• Transmitting Receiving Devices
• Batteries
• Transmission Lines
• First Lines
• Iron Wires - Poor Results
• Copper Wires - Tempted Thieves
• Underground
• Covered With Cotton Pitch
• Insulating Wires In Suspension

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Telegraph Lines

• Ring Insulator (1845)
• Insulator With Tension Devices (1845)
• Porcelein Insulator (1860)

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Machinery Electrical Industry

• Telegraph Produced Numerous Inventions
• Lightning Rods
• Cummutators, Relays, Sound Devices,
  Galvanometers, Measuring Instruments
• Telephone
• New Occupations
• Physicists To Electrical Engineering
• First High Tech Occupation In The West

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Machinery Electrical Industry

• Pixii (1832)
• Magnetoelectric Motor
• Froment (1844)
• Electric Generators
• Shown - Froment
• 8 Soft Iron Hubs
• 4 Elctromagnets
• Adapted (1855)
• Power Clocks In Telegraph Machines

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Telephone

• Robert Hooke (1635-1703)
• Tis not impossible to hear a whisper a furlongs
  distance, it having already been done and
  perhaps the nature of the thing would not make it
  more impossible though that furlong should be ten
  times multiplied
• J. Philipp Reis (1834-1874)
• First Practical Electric Telephone (1861)
• Just A Toy

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Telephone

• 1876
• Alexander Graham Bell - Awarded Patent
• Based On Hermann Helmholtzs Work
• Elisha Gray - Superior Design
• Alexander Graham Bell
• Teacher Of Deaf
• Used No External Power Source
• Still Can Be Used For Short Distances
• Transmitter Receiver Nearly Identical
• Electromagnetic Microphone