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THE MYSTERIOUS DUST DEVIL

                                                     A local whirl of dust, usually not more than a few yards in diameter, in which the particles are swept round and round the centre, and are lifted to considerable heights –sometimes to 2,000 or 3,000 feet above the earth’s surface. It is caused by excessive local heating by the sun in an arid region, a strong convection current being formed. Dust devils usually move over the desert at from 5 to 15 miles per hour, though speeds of over 30 miles per hour are sometimes reached, and as many as five or six of them may often be counted by the observer. Being so limited in size, they are harmless even to aviation.       A storm in which a thick mass of dust obscures the atmosphere, and reduces visibility very considerably –sometimes practically to zero. It causes acute discomfort on the surface, and is a danger to aviation. It is caused by a turbulent wind blowing over an arid, dusty surface, and its approach is usually heralded by

MYSTERY SURROUNDING SATURN

                                                               Have you ever looked at the night sky through a telescope? Many who have can tell you that they still remember the first time they found themselves looking at the planet Saturn. It is almost a startling sight. Against a backdrop of endless black dusted with countless glittering stars, there hangs a luminous orb wreathed with flat, elegant rings!            What are these rings? Back in 1610, when the astronomer Galileo first looked at Saturn through his handmade telescope, the view was so fuzzy that Saturn looked like a planet with ears –a central orb flanked by two smaller ones. As telescopes improved over the years, astronomers saw the rings more clearly, but they still argued over the composition of the rings. Many asserted that the rings were rigid, solid disks. Not until 1895 did astronomers have convincing proof that the rings were composed of many particles of rock and ice.          The book The Far Plane