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ECLIPSES. 



eclipsed. An observer, on the other hand, between d e and d h, would see the 

 lower limb only, the upper limb being eclipsed ; and the eclipse would be 

 greater to each of these observers the nearer their position would be to the 

 point e. To observers between h and Y or g and Y, there would be no eclipse, 

 for no part of the moon would be interposed between them and any part of the 

 sun. 



If the vertex of the cone of the moon's shadow is farther from the moon than 

 the surface of the earth, then there will be a small portion of the earth's sur- 

 face at e within the shadow ; and to an observer within any portion of that 

 surface, the sun will be totally eclipsed ; but if the vertex of the shadow do 

 not reach the earth, then an observer at e will see a ring of the sun, not cov- 

 ered by the moon, surrounding the globe of the moon, and the phenomenon 

 will be what is called an annular eclipse. 



These circumstances will render easily intelligible all the ordinary circum- 

 stances of solar eclipses. It will be readily understood, that while a lunar 

 eclipse is the same to all observers on the earth, a solar eclipse will vary in 

 its magnitude and character with the position of the observer ; the same solar 

 eclipse which at one part of the earth is total or annular, at other parts of the 

 earth is partial in various degrees, and at other parts again is not exhibited 

 at all. 



A natural consequence of the diffusion of knowledge is, that while it lessens 

 the vague sense of wonder, with which singular phenomena in nature are be- 

 held, it increases the feeling of admiration at the harmonious laws, the devel- 

 opment of which renders effects apparently strange and unaccountable easily 

 intelligible. It will be easily imagined what a sense of astonishment, and 

 even terror, the sudden disappearance of an object like the sun or moon must 

 have produced in an age when the causes of eclipses were known only to the 

 learned. Such phenomena were regarded as precursors of divine vengeance. 

 History informs us that in ancient times armies have been destroyed by the 

 effects of the consternation spread among them by the sudden occurrence of an 

 eclipse of the sun. Commanders who happened to possess some scientific 

 knowledge, have taken advantage of it to work upon the credulity of those 

 around them by menacing them with prodigies the near approach of which 

 they were well aware of, illustrating thus, in a singular and perverted manner, 

 the maxim that knowledge is power. Happily, in the present day information 

 is too generally diffused to permit the bulk of mankind to be thus played upon. 



Of all the various phenomena presented by eclipses, that which is transcend- 



