READING

GLASS CAPTURING THE DANCE OF LIGHT A.      Glass, in one form or another, has long been in noble service to hum ans A s one of the m ost widely used of manufacture d materials, and certainly the most versatile, it can be as imposing as a telescope mirror the width of a tennis court or as small and simple as a marble rolling across dirt The uses of this adaptable material have been broadened dramatically by new technologies glass fibre optics — more than eight million miles — carrying telephone and television signals across nations, glass ceramics serving as the nose cones of missiles and as crowns for teeth; tiny glass beads taking radiation doses inside the body to specific organs, even a new type of glass fashioned of nuclear waste in order to dispose of that unwanted material. B.      On the horizon are optical computers These could   store   programs   and   process information by means of light - pulses from tiny lasers - rather than electrons And the pulses would travel ov

The Risks of Cigarette Smoke Discovered in the early 1800s and named nicotianine, the oily essence now called nicotine is the main active ingredient of tobacco. Nicotine, however, is only a small component of cigarette smoke, which contains more than 4,700 chemical compounds, including 43 cancer-causing substances. In recent times, scientific research has been providing evidence that year of cigarette smoking vastly increases the risk of developing fatal medical conditions.  In addition to being responsible for more than 85 per cent of lung cancers, smoking is associated with cancers of, amongst others, the mouth, stomach and kidneys, and is thought to cause about 14 per cent of leukemia and cervical cancers. In 1990, smoking caused more than 84,000 deaths, mainly resulting from such problems as pneumonia, bronchitis and influenza. Smoking, it is believed, is responsible for 30 per cent of all deaths from cancer and clearly represents the most important preventable cause of canc

A spark, a flint:  How fire leapt to life The control of fire was the first and perhaps greatest of   humanity’s steps towards a life-enhancing technology To early man, fire was a divine gift randomly delivered in the form of lightning, forest fire or burning lava. Unable to make flame for themselves, the earliest peoples probabh stored fire by keeping slow burning logs alight or by carrying charcoal in pots. How and where man learnt how to produce flame at will is unknown. It was probably a secondary invention, accidentally made during tool-making operations with wood or stone. Studies of primitive societies suggest that the earliest method of making fire was through friction. European peasants would insert a wooden drill in a round hole and rotate it briskly between their palms this process could be speeded up by wrapping a cord around the drill and pulling on each end. The Ancient Greeks used lenses or concave mirrors to concentrate the sun’s rays and burning glasses were

READING PASSAGE Forests are one of the main elements of our natural heritage. The decline of Europe’s forests over the last decade and a half has led to an increasing awareness and understanding of the serious imbalances which threaten them. European countries are becoming increasingly concerned by major threats to European forest, threats which know no frontiers other than those of geography or climate: air pollution, soil deterioration, the increasing number of forest fires and sometimes even the mismanagement of our woodland and forest heritage. There has been a growing awareness of the need for countries to get together to co-ordinate their policies. In December 1990, Strasbourg hosted the first Ministerial Conference on the protection of Europe’s forest. The conference brought together 31 countries from both Western and Eastern Europe. The topics discussed include the co-ordinated study of the destruction of forest ecosystem. The preparatory work for the conference had been

POPULATION MOVEMENTS AND GENETICS A.     Study of the origins and distribution of human population used to be based on archaeological and fossil evidence. A number of techniques developed since the 1950s, however, have placed the study of these subjects on a sounder and more objective footing. The bet information on early population movements is now being obtained from the ‘archaeology of the living body’, the clues to be found in genetic material. B.      Recent work on the problem of when people first entered the America is an example of the value of these new techniques. North-east Asia and Siberia have long been accepted as the launching ground for the first human colonisers of the New World. But was there one major wave of migration across the Bering Strait into the Americas, or several? And when did this event, or events, take place? In recent years, new clues have come from research into genetics, including the distribution of genetic makers in modern Native Americans.