Scientists in Britain and the United States have been shaking hands.
 
No big deal, one might think, but the men in question were 5,000 km (3,000 miles) apart, connected only by the Internet.

In a technological first, two scientists -- one in London and one in Boston -- picked up a computer-generated cube between them on Tuesday and moved it, each responding to the force the other exerted on it.

The devices allowing them to do it are called phantoms, which re-create the sense of touch by sending small impulses at very high frequencies via the Internet, using newly developed fibre optic cables and high bandwidths.

"The experiment went very well," said Joel Jordan, part of a team of scientists at University College London (UCL) which has teamed up with colleague at Massachusetts Institute of Technology (MIT) to conduct the experiment.

"You can actually feel the object being pushed against your hand," he told Reuters. "We can feel each others' forces."

They plan to conduct a second experiment across an even greater distance -- London to California -- later on Tuesday.

UCL said the secret behind the technology is the speed at which the successive impulses are sent.

"In much the same way that the brain re-interprets still images into moving pictures, the frequencies received by the phantom are similarly integrated to produce the sense of a continuous sensation," a UCL statement said.

Not only can scientists feel the force being exerted by colleagues across the Atlantic Ocean, they can also feel the texture of the object they are feeling.

"You can feel how rough something is, or how springy the side of the cube is," Jordan said.

The implications of the experiment could be vast, said UCL, which described the event as the world's "first transatlantic handshake over the Internet".

For example, trainee surgeons could use it to practice operations via the Internet.

It would also have recreational uses, allowing people to touch and feel each other over the Internet.

"There are certainly strange aspects to this," Jordan said. "You can hit each other hard enough to leave little bruises, and there are bigger versions of the equipment we're using which could really cause some damage."

However, don't expect to find touchy-feely computer software in the shops before Christmas. "I don't think it'll be available to the public for years -- at least five years," Jordan said.