12 Notes on Star-Streams. 



occasion, return to the consideration of the subject. For the 

 present, I will merely note that there are peculiarities in the 

 distribution of double and multiple stars, in the position in 

 which temporary" stars have made their appearance, and in the 

 distribution of nebulae, which seem very worthy of notice. 



One point, however, immediately connected with my sub- 

 ject, remains to be mentioned. I have traced streams of stars 

 more conspicuous than those forming the Milky Way : we have 

 also evidence of streams of light yet more delicate and eva- 

 nescent than the light of our galaxy. In Sir John HerscheFs 

 great work on the southern skies, he notes the frequent recur- 

 rence of " an exceedingly delicate and uniform dotting, or stip- 

 pling of the field of view by points of light too small to admit of 

 any one being steadily or fully examined, and too numerous for 

 counting, were it possible so to view them." In thirty-seven 

 places he detected this remarkable and significant phenomenon ; 

 a phenomenon so faint, that he says, " The idea of illusion has 

 continually arisen subsequently;" an idea well befitting the 

 modesty of the philosophic observer, but which those who 

 appreciate Sir John HerscheFs skill as an observer will be 

 very unwilling to accept. As Professor Nichol remarks, " It is 

 enough to read from HerscheFs note-book — ( I feel satisfied 

 the stippling is no illusion, as its dark mottling moves with 

 the stars as I move the tube to and fro' — to feel convinced 

 that the phenomenon is real.'''' Now, a remarkable fact con- 

 nected with those observations is, that when Sir J. Herschel 

 marked down in a star- chart the places in which he had de- 

 tected this nebulous appearance, he found that, " with the 

 exception of three, which appeared outlying and disconnected, 

 they formed several distinct but continuous streams." 



