E. S. Holden—On supposed changes in Nebida M, 17. 



the [western] angle of the Omega. . . . Under these c 

 the arguments for a real change in the nebula might seem to ha 

 considerable weight. Nevertheless, they are weakened 

 destroyed by a contrary testimony entitled to much relian 



mature death is the more to be regretted, as he was, so far as 



only other recent observer who has given himself 



pressly states that hoili the nebulous knots 



coadjutor Mr. Smith on August 1, 1839, i. e., two 



at to the date of my last drawing. Neither Mr. 



, however, nor any other observer, appears to have had the 



years subsequent to the date of my last drawing. Neith 

 Mason, however, nor any other observer, appei 



3 of the existence of the fainter horseshoe arc attached 



to the [eastern] extremity of Messier's streak, 

 given a figure of this nebula, accompanied by a description. In 

 this figure [our Fig. 3], the nebulous diffusion at the [western] 

 angle and along the [western] base line of the Omega is repre- 

 sented as very conspicuous ; indeed, much more so than 1 can per- 

 suade myself it was his intention it should appear." 



