Glass, in one form or another, has long been in nobleservice to humans As one of the most widely usedof manufactured materials, and certainly the mostversatile, it can be as imposing as a telescope mirrorthe width of a tennis court or as small and simple asa marble rolling across dirt The uses of thisadaptable material have been broadeneddramatically by new technologies glass fibreoptics — more than eight million miles —carrying telephone and television signalsacross nations, glass ceramics serving as thenose cones of missiles and as crowns forteeth; tiny glass beads taking radiation dosesinside the body to specific organs, even a newtype of glass fashioned of nuclear waste inorder to dispose of that unwanted material.B On the horizon are optical computers Thesecould store programs and processinformation by means of light - pulses fromtiny lasers - rather than electrons And thepulses would travel over glass fibres, notcopper wire These machines could functionhundreds of times faster than today’selectronic computers and hold vastly moreinformation Today fibre optics are usedto obtain a clearer image of smaller andsmaller objects than ever before - even bacterial81viruses. A new generation of opticalinstruments is emerging that can providedetailed imaging of the inner workingsof cells. It is the surge in fibre optic useand in liquid crystal displays that has setthe U.S. glass industry (a 16 billion dollarbusiness employing some 150,000workers) to building new plants to meetdemand.C But it is not only in technology andcommerce that glass has widened itshorizons. The use of glass as art, atradition spins back at least to Romantimes, is also booming. Nearlyeverywhere, it seems, men and womenare blowing glass and creating works ofart. «I didn’t sell a piece of glass until1975,» Dale Chihuly said, smiling, forin the 18 years since the end of the dryspell, he has become one of the mostfinancially successful artists of the 20thcentury. He now has a new commission- a glass sculpture for the headquartersbuilding of a pizza company - for whichhis fee is half a million dollars.D But not all the glass technology thattouches our lives is ultra-modern.Consider the simple light bulb; at the turnof the century most light bulbs were handblown, and the cost of one was equivalentto half a day’s pay for the average worker.In effect, the invention of the ribbonmachine by Corning in the 1920s lighteda nation. The price of a bulb plunged.Small wonder that the machine has beencalled one of the great mechanicalachievements of all time. Yet it is verysimple: a narrow ribbon of molten glasstravels over a moving belt of steel inwhich there are holes. The glass sagsthrough the holes and into waitingmoulds. Puffs of compressed air thenshape the glass. In this way, the envelopeof a light bulb is made by a singlemachine at the rate of 66,000 an hour, ascompared with 1,200 a day produced bya team of four glassblowers.E The secret of the versatility of glass liesin its interior structure. Although it isrigid, and thus like a solid, the atoms arearranged in a random disordered fashion,characteristic of a liquid. In the meltingprocess, the atoms in the raw materialsare disturbed from their normal positionin the molecular structure; before theycan find their way back to crystallinearrangements the glass cools. Thislooseness in molecular structure givesthe material what engineers calltremendous “formability” which allowstechnicians to tailor glass to whateverthey need.F Today, scientists continue to experimentwith new glass mixtures and buildingdesigners test their imaginations withapplications of special types of glass. ALondon architect, Mike Davies, seeseven more dramatic buildings usingmolecular chemistry. “Glass is the greatbuilding material of the future, the«dynamic skin»,’ he said. “Think of glassthat has been treated to react to electriccurrents going through it, glass that willchange from clear to opaque at the pushof a button, that gives you instantcurtains. Think of how the tall buildingsin New York could perform a symphonyof colours as the glass in them is madeto change colours instantly.” Glass asinstant curtains is available now, but thecost is exorbitant. As for the glasschanging colours instantly, that maycome true. Mike Davies’s vision mayindeed be on the way to fulfilment.
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