:28 IN STARRY REALMS. 



first time should not, strange to say, direct the telescope 

 at the nebula ; the instrument should rather be pointed at 

 the heavens, just a little to the west of the nebula. The 

 clock driving the equatorial should not be started, and the 

 observer should take his seat and look through the eye- 

 piece before the nebula has entered the field. He will 

 see, no doubt, a few stars on the black background, which 

 gradually pass in procession across his field of view. 

 This is merely the ordinary diurnal journey of the heavens, 

 by which all the objects move slowly from east to west ; I 

 ought rather to say appear to move, for of course the 

 motion on the heavens is only apparent, the fact being 

 that it is the earth which is turning around. 



After the observer's eye for a minute or so has become 

 familiarised with the dark aspect of the heavens under 

 ordinary circumstances, he will begin to perceive on the 

 eastern side (it will appear in the telescope no doubt as on 

 the western side) a faint dawn of light. Gradually there 

 will steal across his field of view a sort of ghostlike lumi- 

 nosity that is in marked contrast to the darkness in the 

 rest of the field ; as the seconds move on, this object will 

 disclose itself until the full splendour of the Great Nebula 

 comes into view ; then the entire field will be filled with 

 the light, and then it will gradually advance and gradu- 

 ally pass away again to emphasize the contrast between 

 the brilliance of the nebula and the darkness of the sky. 

 Unless this method is adopted, the full interest of a tele- 

 scopic yiew of the Great Nebula is not attained, for when 

 the entire field is full of the glow the beginner will hardly 

 recognise the nebula. He will be apt to think that the 

 fainter part of the field he sees is the ordinary ground- 



