THE CONSTELLATIONS. 119 



rays which enter the eye cannot have been less than six 

 years and four months and a half coming from that star to 

 the observer. Henceit follows that when we see an object 

 at the calculated distance, at which one of these very remote 

 nebulae may still be perceived, the rays of light which con- 

 vey its image to the eye, must have been more than nineteen 

 hundred and ten thousand, that is, almost two millions of 

 years on their way ; and that, consequently, so many years 

 ago, this object must already have had an existence in the 

 sidereal heavens, in order to send out those rays by which 

 we now perceive it. 



But when we have reached the utmost distance to which 

 the power of our instruments can penetrate, who will say, 

 that we are approaching any limits of the creation 1 who 

 will say, that if the disembodied spirit should travel forward 

 through eternity, numberless systems would not be continual- 

 ly spreading before it ? All that part of the universe which 

 we are able to discern, is peopled by inhabitants, who have 

 the common want of heat and light ; who will say, that 

 there are not other parts of the material universe inhabited 

 by beings of different natures, to whom these wants are un- 

 known ? It is only some pontion, we know not how small, 

 of the material universe which is obvious to our senses ; 

 who will attempt to define the limits of the invisible world ? 

 who will attempt to set bounds to the works of infinite power 

 and infinite goodness? 



Questions. — 1. What are fixed stars? — why so called? 2. How 

 docs it appear that they do not borrow their light ? 3. What is said 

 of the magnitude of the stars ? 4. Number? 5. Describe the milky- 

 way (or galaxy.) 6. What calculations did Dr. Herschel make ? 

 [Note. Many stars, single to the naked eye, appear double, triple, 

 and even quadruple, through a telescope. Dr. Herschel found that in 

 more than fifty double stars, a change of situation really takes place • 

 it is concluded, therefore, that they describe orbits round a centre of 

 gravity.] 



LESSON 55 



The Constellations 



The first people who paid much attention to the fixed 

 stars were the shepherds in the beautiful plains of Egypt 



