THE GREAT NEBULA IN ORION. 91 



would give under the most favourable circumstances. 

 And in like manner, the performance of Lord Rosse s 

 telescope on the Orion nebula has been surpassed so 

 far as resolution into discrete stars is concerned by 

 the exquisite denning power of the noble refractor of 

 Harvard College (U.S.). By means of this instrument 

 hundreds of stars have been counted within the confines 

 of the once intractable nebula. 



It seemed, therefore, that all doubt had vanished 

 from the subject which had so long perplexed astrono 

 mers. That was proved to be real, Nichol wrote, 

 which, with conceptions of space enlarged even as 

 Herschel s, we deemed incomprehensible. 1 



Yet even at this stage of the inquiry there were 

 found minds bold enough to question whether a per 

 fectly satisfactory solution of the great problem had 

 really been attained. Nor is it difficult, I think, to 

 point out strong reasons for such doubts. I shall con 

 tent myself by naming one which has always appeared 

 to me irresistible. 



The Orion nebula as seen in powerful telescopes 

 covers a large extent of the celestial sphere. According 

 to the Padre Secchi, who observed it with the great 

 Merz refractor of the observatory at Rome, the nebulous 

 region covers a triangular space, the width of whose 

 base is some eight times, while its height is more than 

 ten times as great as the moon s apparent diameter, a 

 space more than fifty times greater than that covered 

 by the moon. Now, I do not say that it is inconceivable 

 that an outlying star-system, so far off as to be irre- 



