tailieunhanh - Gre verbal section10

Tham khảo tài liệu 'gre verbal section10', ngoại ngữ, anh ngữ phổ thông phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | THE GRE VERBAL SECTION The discovery that shows beyond all others that Hipparchus possessed one of the masterminds of all time was the detection of that remarkable celestial movement known as the precession of the equinoxes. The inquiry that led to this discovery involved a most profound investigation especially when it is remembered that in the days of Hipparchus the means of 5 observation of the heavenly bodies were only of the rudest description and the available observations of earlier dates were extremely scanty. We can but look with astonishment on the genius of the man who in spite of such difficulties was able to detect such a phenomenon as the precession and to exhibit its actual magnitude. I shall endeavor to explain the nature of this singular celestial movement for it may be said to offer the first instance in the 10 history of science in which we find that combination of accurate observation with skillful interpretation of which in the subsequent development of astronomy we have so many splendid examples. The word equinox implies the condition that the night is equal to the day. To a resident on the equator the night is no doubt equal to the day at all times in the year but to one who lives 15 on any other part of the Earth in either hemisphere the night and the day are not generally equal. There is however one occasion in spring and another in autumn on which the day and the night are each twelve hours at all places on the Earth. When the night and day are equal in spring the point which the sun occupies on the heavens is termed the vernal equinox. There is similarly another point in which the sun is situated at the time of the autumnal 20 equinox. In any investigation of the celestial movements the positions of these two equinoxes on the heavens are of primary importance and Hipparchus with the instinct of genius perceived their significance and commenced to study them. It will be understood that we can always define the position of a point on the .