Science Fiction
Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Latest By
Category:
Armor
Artificial
Intelligence
Biology
Clothing
Communication
Computers
Culture
Data Storage
Displays
Engineering
Entertainment
Food
Input Devices
Lifestyle
Living Space
Manufacturing
Material
Media
Medical
Miscellaneous
Robotics
Security
Space Tech
Spacecraft
Surveillance
Transportation
Travel
Vehicle
Virtual
Person
Warfare
Weapon
Work
"The answer to the problem of information overload on the Net is reputations… engineer a system called a reputation server."
- Neal Stephenson
 |
| Electrified Fence | ||
| A wire fence carrying an electrical charge sufficient to deter crossing the boundary. |
| Well, how have you arranged the fence?"
"I start twelve immensely strong wires--naked, not insulated --from a big dynamo in the cave--dynamo with no brushes except a positive and a negative one--" "Yes, that's right." "The wires go out from the cave and fence in a circle of level ground a hundred yards in diameter; they make twelve independent fences, ten feet apart--that is to say, twelve circles within circles--and their ends come into the cave again." "Right; go on." "The fences are fastened to heavy oaken posts only three feet apart, and these posts are sunk five feet in the ground." "That is good and strong." "Yes. The wires have no ground-connection outside of the cave. They go out from the positive brush of the dynamo; there is a ground-connection through the negative brush; the other ends of the wire return to the cave, and each is grounded independently." "No, no, that won't do!" "Why?" "It's too expensive--uses up force for nothing. You don't want any ground-connection except the one through the negative brush. The other end of every wire must be brought back into the cave and fastened independently, and _without_ any ground-connection. Now, then, observe the economy of it. A cavalry charge hurls itself against the fence; you are using no power, you are spending no money, for there is only one ground-connection till those horses come against the wire; the moment they touch it they form a connection with the negative brush _through the ground_, and drop dead. |
| From A Connecticut Yankee in King Arthur's Court,
by Mark Twain. Published by Not known in 1889 Additional resources -
|
Many sources credit Twain as the earliest source for this idea - but I think there is at least one earlier reference that should count.
In his 1875 epic 20,000 Leagues Under the Sea, Jules Verne writes about electrifying a stair rail or cable to prevent unwanted intrusions onto the Nautilus.
Comment/Join this discussion ( 2 ) | RSS/XML | Blog This |
Additional
resources:
More Ideas
and Technology from A Connecticut Yankee in King Arthur's Court
More Ideas
and Technology by Mark Twain
Tech news articles related to A Connecticut Yankee in King Arthur's Court
Tech news articles related to works by Mark Twain
Electrified Fence-related
news articles:
- Pub Installs Electrified Fence Around Bar
| Flimmer Navy Drone Flies And Swims |
| Indian Court Says Brain Scan Proves Murder |
| Background Draw-a-Secret (BDAS) Makes Graphical Passwords |
| ID-U Biometrics Eye Tracking Signature |
Want to Contribute an
Item?
It's easy:
Get the name of the item, a
quote, the book's name and the author's name, and Add
it here.
| <Previous | Next> |
|
|
|
Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Science Fiction Invention Timeline, or see what's New.
|
Science Fiction
Timeline
1600-1899
1900-1939
1940's 1950's
1960's 1970's
1980's 1990's
2000's 2010's
'the registration number which the traffic control automatically photographed as she left the controlway...'
'It could maintain a steady six miles per hour...'
'Then they press one of these here thirteen buttons...'
'...without burning a single hydrocarbon molecule to injure the diseased atmosphere any further.'
'Bird-like robots now descended from the ceiling of the theatre...'
'The efficient robot waiter of the Sky Club had cleared away the remnants of an epicurean meal.'
'...in the tank the new body and the new mind and memory and life has taken almost instant form.'
'pirate three-vee satellites sanded out of orbit...'
'The atmosphere yielded its moisture with reluctance. It had to be coaxed down...'
