Im struggling to understand the idea, and for a start do not have any knowledge of an electromagnet. its a magnet powered by electristy? and the wires, wires inside the electromagnet or wires externaly? could you say that in a tad more simplicity :)

i understand about wires and the speed of transmission in them, i understand the speed of sound,

'you triumphantly watch the electromaget's weight drop 330 m away at the same time as your weight hits your other toe again.'

So, originally you have both the weights close together with wire 330m long but not in a straight line. and after you straighten the line so that the weights are 330m apart and the line is straight, i think i understand that. But what has that to do with being on the phone to someone. i do think i understand but am a little unsure.

http://en.wikipedia.org/wiki/Electromagnet

As usual, let us know if that is a problem. It was to do with one of the most important demonstrations in the history of technology: Michael Faraday showed that an electric current could move magnets, and magnets could move electric currents. Big deal! Great big hairy deal!!! Couldn't please expensive damfool scientists do something useful with all the money and time they waste?

And yet, that demonstration in the end formed the basis for every electric bell, every electric motor, the every telephone, every dynamo, every practical television set or computer you ever saw or heard of.

It would not be possible for you to take a cent or a billion dollars to the nearest shop to buy anything that was not affected by that discovery, whether a blade of grass or a Boeing.

But never mind that; do a quick survey at school and see what percentage of the people you know, whether pupils or teachers, think that such things are anything but boring and irrelevant.

Anyway, you are quite right; yes an electromagnet is in fact a means by which you can use magnetism at a distance to move things, and do so pretty quickly; far more quickly than sending a servant or a dog to do it, or even shouting at someone to do it.

But yes, you have the general idea. By switching the current where you are, you can make sounds at a distance, far faster than you can send the sounds that distance. The electric current carried the necessary information to make the sounds; it did not carry the sounds themselves. If you can grab that idea, you have it made.

Leave it at that for now. If you could master the idea of surface tension as you did, I am sure that you can master the idea of sending information rather than sending a vibration through the air. I doubt that you would ever want to read a book called “The Sirens of Titan” by Kurt Vonnegut, but he wrote about the grandest theme along those lines that ever I read.

Jon peaked my magnetic vibes with his list of magnet uses.My son worked in the magnet production business, in China,for several years.  I must tell you about a company here inNorfolk, VA USA that makes water "cleaners" by passing thewater over an array of cheap ceramic magnets.  His units areused in commercial Air Cond. systems and steam boilers to prevent scale buildup.  Given some time existing scale willbe 'reasorbed' by the system.  The highly advertised devicesthat are a clamp on the pipe unit are nothing.Here is the web address for Descal-a-matic.  See  commentsof many users.

http://www.descal-a-matic.com/   They ship worldwide

One company that bottles drinking water, the craze, put oneof the company's units before a large reverse osmosis filter.The life of this expensive filter was extended quite a bit.

A Google search of desca-a-matic will give interesting hits.

Paul