9781422277614

Chapter Seeing More Clearly 1 Early in 1609, rumors began circulating around Europe of a new and marvelous instrument. A Flemish optician had, it seemed, “found the art of seeing far places and things as if nearby.” The news spread quickly. In April, “glasses of a new invention” had reached Paris and, by May, as far as Milan. Spectacle-makers tried to discover the “secret” for themselves. At the end of July there was news that the Flemish optician was on his way to Venice. He was bringing a “perspective glass” with him, hoping to sell it to the authorities for a large sum of money. That man was possibly Hans Lippershey, from Middleburg in Flanders (present-day Belgium). Although no one will ever be quite sure, he is often credited as the inventor of the first useful telescope. Visiting Venice at that time was a middle-aged professor of mathematics from Padua University named Galileo Galilei. He was a short, stocky man with red hair, who at the time was concerned with the laws of motion. But when he heard of the arrival in Italy of that “certain Fleming,” and of what he was bringing with him, his imagination was fired. He rushed from Venice to intercept the man and find out more about his “spyglass,” but they never met. When Galileo returned to Padua, he worked out the principles for himself. It took him a single day. He made a telescope and, more importantly, he discovered the optical principles upon which it worked. He used a combination of a weak convex lens and a strong concave lens . This arrangement is now known as the “Galilean” type of telescope.

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