دانلود کتاب History of Astronomy

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: fifth century B.c. [the present reformed Jewish calendar dating from the fourth century A.d.], a date a " little more than a century after the grandfathers and great-grandfathers of those whose business is recorded had fled into Egypt with Jeremiah " (Sayce); and (2) that the order of intercalation at that time was not dissimilar to that in use at the present day. Then again, Knobel reminds us of " the most interesting discovery a few years ago by Father Strassmeier of a Babylonian tablet recording a partial lunar eclipse at Babylon in the seventh year of Cambyses, on the fourteenth day of the Jewish month Tammuz." Ptolemy, in the Almagest (Suntaxis), says it occurred in the seventh year of Cambyses, on the night of the seventeenth and eighteenth of the Egyptian month Phamenoth. Pingre and Oppolzer fix the date July 16th, 533 B.c. Thus are the relations of the chronologies of Jews and Egyptians established by these explorations. 3. Ancient Greek Astronomy. We have our information about the earliest Greek astronomy from Herodotus (born48oB.C.). He put the traditions into writing. Thales (639-546 B.c.) is said to have predicted an eclipse which caused much alarm, and ended the battle between the Medes and Lydians. Airy fixed thedate May 28th, 585 B.c. But other modern astronomers, give different dates. Thales went to Egypt to study science, and learnt from its priests the length of the year (which was kept a profound secret!), and the signs of the zodiac, and the positions of the solstices. He held that the sun, moon, and stars are not mere spots on the heavenly vault, but solids; that the moon derives her light from the sun, and that this fact explains her phases; that an eclipse of the moon happens when the earth cuts off the sun's light from her. He supposed the earth to...