MILKY WAY. 



197 



Herschel, a twenty-feet instrument penetrates 900, and a 

 forty-feet one 2800 distances of Sirius) the Milky Way 

 appears as diversified in its sidereal contents as it is irregular 

 and indefinite in its outlines and limits when seen by the un- 

 aided eye. While in some parts the Milky Way exhibits, 

 throughout a large space, the greatest uniformity in the light 

 and apparent magnitudes of the stars, in others the most 

 brilliant patches of closely-crowded luminous points are inter- 

 rupted by granular or reticular darker 87 intervals containing 

 but few stars ; and in some of these intervals in the interior 

 of the Galaxy not the smallest star (of the 18m. or 20m.) is 

 to be discovered. It almost seems as though, in these regions, 

 we actually saw through the whole starry stratum of the 

 Milky Way. In gauging with a field of view of 15' diameter, 

 fields presenting on an average forty or fifty stars are almost 

 immediately succeeded by others exhibiting from 400 to 500. 

 Stars of the higher magnitudes often occur in the midst of the 

 most minute telescopic stars, whilst all the intermediate classes 

 are absent. Perhaps those stars which we regard as be- 

 longing to the lowest order of magnitudes do not always ap- 

 pear as such, solely on account of their enormous distance, but 

 also because they actually have a smaller volume and less con- 

 siderable development of light. 



In order rightly to comprehend the contrast presented by the 

 greater brilliancy, abundance, or paucity of stars, it will be ne- 

 cessary to compare regions most widely separated from each other. 

 The maximum of the accumulation and the greatest lustre of 

 stars are to be found between the prow of Argo and Sagittarius, 

 or, to speak more exactly, between the Altar, the tail of the 

 Scorpion, the hand and bow of Sagittarius, and the right foot 

 of Ophiuchus. " No region of the heavens is fuller of objects, 



57 " Intervals absolutely dark and completely void of any star 

 of the smallest telescopic magnitude." Outlines, p. 536. 



