NOTES ON NEBULA. 127 



adapted to grasp all the feeble rays of light that these ob- 

 jects diffuse, and concentrate them so as to produce an 

 image bright enough to admit of being observed. 



The most glorious constellation of stars in the firmament 

 is undoubtedly that of Orion. This splendid group is seen 

 in the south during the winter months, and towards the 

 close of January it is situated in a very convenient posi- 

 tion for observing early in the evening. The group is 

 specially characterized by the number of unusually bright 

 stars which it includes, and the three stars in the centre, 

 forming the so-called Belt of Orion, is as well known a 

 celestial figure as the sky contains. Directly under the 

 belt are three much smaller stars nearly in a line, which 

 points straight upwards to the middle star of the belt. 

 Those three lower stars are usually known as the sword 

 handle of Orion, this being the position which they occu- 

 pied in the fanciful old sketches of the constellation. The 

 three stars of the sword handle of Orion are plunged in 

 the Great Nebula. This object cannot be seen by the un- 

 assisted eye, though doubtless around the central star a little 

 haziness is perceptible, and even the slightest telescopic 

 aid will suffice to indicate that the central star of the 

 sword handle is attended by a surrounding glow of light, 

 which renders it quite unlike other stars. This can indeed 

 be sufficiently shown with an ordinary opera-glass, one 

 glance through which will awaken in the beholder a keen 

 desire to study the object under more favourable condi- 

 tions. But to do justice to the object, telescopes of large 

 power are desirable. 



To realise fully the magnificence of the Great Nebula, 

 the observer who is being introduced to the object for the 



