"Telescopic Work for Starlight Evenings" by William F. Denning. Published by Good Press. Good Press publishes a wide range of titles that encompasses every genre. From well-known classics & literary fiction and non-fiction to forgotten−or yet undiscovered gems−of world literature, we issue the books that need to be read. Each Good Press edition has been meticulously edited and formatted to boost readability for all e-readers and devices. Our goal is to produce eBooks that are user-friendly and accessible to everyone in a high-quality digital format.
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William F. Denning. Telescopic Work for Starlight Evenings
Telescopic Work for Starlight Evenings
Table of Contents
CHAPTER I. THE TELESCOPE, ITS INVENTION AND THE DEVELOPMENT OF ITS POWERS
CHAPTER II. RELATIVE MERITS OF LARGE AND SMALL TELESCOPES
CHAPTER III. NOTES ON TELESCOPES AND THEIR ACCESSORIES
CHAPTER IV. NOTES ON TELESCOPIC WORK
CHAPTER V. THE SUN
CHAPTER VI. THE MOON
CHAPTER VII. MERCURY
CHAPTER VIII. VENUS
CHAPTER IX. MARS
CHAPTER X. THE PLANETOIDS
CHAPTER XI. JUPITER
CHAPTER XII. SATURN
CHAPTER XIII. URANUS AND NEPTUNE
CHAPTER XIV. COMETS AND COMET-SEEKING
CHAPTER XV. METEORS AND METEORIC OBSERVATIONS
CHAPTER XVI. THE STARS
CHAPTER XVII. NEBULÆ AND CLUSTERS OF STARS
Index
FOOTNOTES
Отрывок из книги
William F. Denning
Published by Good Press, 2019
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Gregorian Telescope.
The idea of reflecting-telescopes received mention as early as 1639; but it was not until 1663 that Gregory described the instrument, formed of concave mirrors, which still bears his name. He was not, however, proficient in mechanics, and after some futile attempts to carry his theory into effect the exertion was relinquished. In 1673 Cassegrain revived the subject, and proposed a modification of the form previously indicated by Gregory. Instead of the small concave mirror, he substituted a convex mirror placed nearer the speculum; and this arrangement, though it made the telescope shorter, had the disadvantage of displaying objects in an inverted position. But the utility of these instruments was not demonstrated in a practical form until 1674, when Hooke, the clever mechanician, gave his attention to the subject and constructed the first one that was made of the kind.
