64 LIGHT SCIENCE FOR LEISURE HOURS. 



Maclear : ' Knowing that an unfavourable sky would 

 render observations with a powerful spectroscope quite 

 impracticable, I desired Captain Maclear to observe 

 with a small direct-vision Browning spectroscope, 

 attached to a four-inch telescope, mounted equatorially.' 

 The spectroscope was so placed that the light coming 

 from a portion of space outside the sun, and directed 

 towards his centre, was under examination. Of course, 

 while the sun's direct light was falling on the air 

 lying in this direction, the spectroscope showed the 

 ordinary solar spectrum, precisely as when one of these 

 handy direct-vision spectroscopes is turned towards the 

 sky in the daytime. But ' immediately totality com- 

 menced,' proceeds Father Perry, ' the ordinary solar 

 spectrum was replaced by a faint diffused light and 

 bright lines ' (whose position he indicates). ' There 

 were no dark lines that is to say, none of those lines 

 which are present in the solar spectrum.' Then follows 

 the most important part of the account. The spec- 

 troscope was directed Ho a distance of about eight 

 minutes,' or half the moon's apparent radius, from the 

 edge of the moon's disc. ' The same lines remained 

 visible.' * The centre of the moon was then tried, and 

 the bright lines were still seen, but only half as strong 

 as before.' The spectroscope was then again directed 

 to a point eight minutes outside the moon, and the 

 lines were restored to their original brightness. 



These results require to be considered somewhat 

 carefully. The reader cannot fail to be surprised by 

 the fact that, from the direction in which lay the centre 



