(Source: Frank Ogden, The Last Book You'll Ever Read,
 Toronto: MacFarlane, Walter and Ross, 1993, p. 206.)


 Ferrofluids
 
 
 Almost everyone knows about solid-state technology, which
 greased the tracks for the high-speed growth of the computer
 and microchip industry. Now prepare for liquid-state
 technology, a new class of materials unknown in nature.
 Ferrofluids are a completely new type of material. They give
 us liquid magnetism.

 
  Ferrofluids have unique properties. They contain
 microscopic magnetic particles, each about 6,200 times
 smaller than a human hair. When these particles are
 influenced by a magnetic field they defy gravity and can
 take the shape of their container, go upward, turn corners.
 Manipulation of the magnetic field directs the flow. A fluid
 in a dish can jump out toward a nearby magnet!


   If an object heavier than the fluid itself is placed into
 a ferrofluid, instead of sinking to the bottom the object
 becomes buoyant and drifts toward the center of the
 container. There are considerable advantages to such a
 material. In South Africa one innovative company is using
 this "selective buoyancy" to pick out diamonds from beach
 sand.

 
  Liquid magnetism is an answer just waiting for the right
 questions to be asked. As a sealant a ferrofluid appears to
 have no competitors. Just the thing to have around entrances
 during chemical or biological warfare attacks. In a solar
 heating system a ferrofluid could drive its own circulation.
 In medicine ferrofluids may be the new drug-delivery system.
 A ferrofluid carrying a site-specific drug could be guided
 to its location directly and held there by a magnetic field
 until its timed dispersal.

 
  This could be more than a new discovery -- it could be the
 start of a new industry.