KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 60. N:0 8- 



53 



clouds in the Milky Way form a unit of far greater dimensions than those derived 

 for the spiral nebula?, with aid of the parallaxes determined by Wolf. Moreover, 

 Wolf remarks that the diameters of the examined spiral nebula?, calculated to about 

 1000 light-years, turn out surprisingly small. On the other hand, the values of the 

 parallaxes for the Orion nebula and Nova Persei are possibly somewhat too great. 

 As to the latter, we find ~ = 0",oio out of the five determinations used in the following 

 discussion of the appearance of Novse in the spiral nebula?. As it has not been 

 possible to take into consideration two determinations leaving negative values (Aitken 

 and Hartwig), it is probable that the parallax is in reality smaller than the value 

 employed here. 



8. The Appearance of Novce in the Spiral Nebulce. 



In 1885 Hartwig, among others, found a nova of the seventh magnitude close 

 to the centre of the Andromeda nebula, and in 1895 Mrs Fleming communicated the 

 discovery of a nova which had appeared near the nucleus of the spiral nebula N. G. C. 

 5243. Since 1916 American astronomers, in examining long-exposure plates of spiral 



Table XIII. 





Object 



Date of 

 observed 

 maximum 



Time of 

 discovery 



w max. 



Distance 



from 

 nucleus 



Discoverer 



Authority 



1 



N. G. C. 224 



Aug. 



1885 



1885 



a/ 

 7,2 



16" 



Hartwig others 



A.N. 112:245 



2 



5253 



July 



1895 



1895 



7,2 



32 



Mrs Fleming 



Harv. Circ. No. 4 



3 



4321 



Mar. 



1901 



1917 



13,5 



110 



Curtis 



L. O. B. No. 300 



4 



3147 



Apr. 



1904 



— 



13-14 



340 



Mrs Isaac Roberts 



P. A. S.P. 29: 214 



5 



224 



Sept. 



1909 



1917 



16,3 



249 



Ritchey 



P. A.S.P. 25:211 — 12 



6 



224 



Sept. 



1909 



1917 



17,0 



198 





P. A. S.P. 29:211 — 12 



7 



2841 



Feb. 



1912 



1917 



16 



54 



Pease 



P.A. S.P. 29.213 



8 



4321 



Mar. 



1914 



1917 



14 



111 



Curtis 



L. O. B. No. 300 



9 



4527 



Mar. 



1915 



1917 



14 



45 



» 



L. O. B. No. 300 



10 



6946 



July 



1917 



1917 



14,6 



111 



Ritchey 



P. A.S.P. 29:213; Sirius 1918 



11 



224 



Sept. 



1917 



1917 



17,5 



600 



Shapley 



P. A.S.P. 29:213 



12 



224 



Oct. 



1917 



1917 



18,0 



227 



Ritchey 



P.A. S.P. 30:162—03 



13 



224 



Nov. 



1917 



1917 



16,8 



321 



» 



P.A. S.P. 30:162—63 



14 



224 



Jan. 



1918 



1918 



17,1 



143 



» 



P. A.S.P. 30:162—63 



15 



224 



Feb. 



1918 



1918 



17,7 



123 



» 



P. A. S. P. 30: 162—63 



IG 



224 



Feb. 



1918 



. 1918 



17,2 



550 



Duncan 



P.A. S.P. 30:255 



17 



224 



Oct. 



1918 



1918 



17,3 



466 



Sanford 



P.A. S.P. 30:341 



18 



224 



Oct. 



1918 



1918 

 S u 



17,0 

 s p e c 1 



380 

 ed O 



b j e c t s 



» » 





224 





1664 



— 



6,0? 



~~ 



Bullialdus 



See Bibliography No. 29 





3031 



Feb. 



1910 



1917 



18? 



— 



Ritchey 



P.A. S.P. 29:210—12 





2403 



Feb. 



1910 



1917 



16,5? 





» 



» » 





5457—8 



May 



1915 



1917 



18,5? 



— 



» 



» » 





5457-8 



May 



1915 



1917 



19? 



550 



» 



» )> 



