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Wednesday 20 June 2012

we learn about the telephone (1965)



via brainpickings

what did people do before the telephone?


by sending runners with messages


then they discovered they could ride horses


smoke messages, flashing mirrors, blinking lights at night


then the telegraph


then the telephone - how does that work
- sounds make sound waves that vibrate through the air
- when they reach the ear of another the ear drum moves back and forth
- speaking into the phone - the sound waves go into the telephone which make the electrical current alter - which is then sent down the wire to vibrate the receiving plate at the receiving end


then some telephone etiquette and advice
- don't shout use you normal voice
- using the dialing mechanism properly
- don't wait too long to answer
- and let it ring 8 to 10 times
- speak clearly
- don't hog the phone
- using the telephone book 
- and having your own one for numbers you use frequently
- how to call the police in an emergency


humans are also working with satellites sending messages











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