The Telescope

The telescope has changed the world greatly by being able to make distant objects appear closer and more distinct. It helped scientists to discover things that could not be seen by the naked eye. For example, a lot of things in space would have not been discovered if it were not for the telescope. Also, it helped the world of eyesight. It would not only let you see objects from far away, it would also help you see if you had a problem with it. It could also be used for other things: hunting, war, and making new discoveries. What would the world be like without the telescope?

I don't know what the world would be like, but I some very good reasons why it was good that the telescope was created. Before there was the telescope people had to make discoveries by judgment. They were not very accurate discoveries. They also had to just use the naked eye when they would have to use the naked eye when looking at distant objects that could have been easily seen by the telescope. The telescope was one of the main instruments of what has been called the Scientific Revolution of the seventeenth century. It revealed unsuspected phenomena in the heaves and had a profound influence on the controversy between followers of the traditional astronomy, the cosmos, and those who favored the naked eye. It was the first extension of man's senses and demonstrated that ordinary observers could see things that Aristotle had not dreamed of. It therefore helped shift authority in the observation of nature from men to instruments. In short, it was the prototype of modern scientific instruments. But the telescope was not the invention of scientists; rather, it was the product of craftsmen. For that reason, much of it's origin is inaccessible to us since craftsmen were by large illiterate and therefore historically often invisible.

Although the magnifying and diminishing properties of the convex and concave transparent objects was known in Antiquity, lenses, as we know them, were introduced in the West at the end of the thirteenth century. Glass of reasonable quality had become relatively cheap and in the major glass-making centers of Venice and Florence techniques for grinding and polishing glass had reached a high state of development. Now one of the main problems faced by aging scholoars could be solved. With age, the eye progressively loses its power to accommodate, that is, to change its focus from faraway objects to nearby ones. This condition becomes noticeable for most people in their forties, when they can no longer focus on letters held at a comfortable distance from the eye. Magnifying glasses became common in the thirteenth century, but these are cumbersome, especially when one is writing. Craftsmen in Venice began to make small disks of glass, convex on both sides that could be worn in a frame-spectacles. Because these little disks were shaped like lentils, they became known as "lentils of glass," or (from the Latin) lenses. The earliest illustrations of spectacles date from about 1350, and spectacles soon came to be symbols of learning.

These spectacles were, then, reading glasses. When someone had trouble reading, one went to a spectacle-maker's shop or a peddler of spectacles and found the suitable pair by trial and error. They were, by large, glasses for the old. Spectacles for the young, concave lenses that correct the refractive error known as myopia were first made (again in Italy) in the middle of the fifteenth century. So by about 1450 the ingredients for making a telescope were there. Several combinations of convex and concave mirrors and lenses can achieve the telescope effect. Why was the telescope not invented in the fifteenth century? There is no good answer to this question, except perhaps that the lenses and mirrors of the appropriate strengths not available until later.

In the book of white magic, that was very popular in the sixteenth century, there are several

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