44 NATURAL THEOLOGY. 



To conclude : In astronomy, the great thing is 

 to raise the imagination to the subject, and that 

 oftentimes in opposition to the impression made 

 upon the senses. An illusion, for example, must 

 be gotten over arising from the distance at which 

 we view the heavenly bodies, viz. the apparent 

 slowness of their motions.'^ The moon shall take 



*2 This cut represents the coaut of Ibll, the fixed stars being 

 seen through its tail, which extended J 23,000,000 of miles. The 

 period of its revohition is calcuhited at above 3,300 years. The 

 great comet of 1680 was calculated by Sir Isaac Newton to have 

 a tail of 80,000,000 of miles, immediately af er its perihelion, a 

 periodic time of 575 years, and a velocity, when nearest the sun, 

 of 880,000 miles in an hour. Its orbit is so much elongated that 

 its greatest distance from the sun is estimated at near 3,000 mil- 

 lions of miles, and its least at only J 50,000 miles. Halley's comet, 

 which appeared in 1682, 1759, and 1835, — probably also in 1531 



rial universe, and conduct its various motions, are very different 

 from those which were necessary to have produced it from nothing, 

 or to have disposed it in the admirable form in which it now pro- 

 ceeds." — JMadaiirbi's Account of J^ewtoiCs Philosophy, p. 407. 

 ed. 3. 



