XVI.] THE DISTRIBUTION OF CHEMICAL GROUPS OF STARS. 137 



some they are more interesting than all the other stars in the heavens, 

 because they are the mysterious " new stars," which have been supposed 

 to be new creations. When we come to examine these so-called new 

 stars we find that they also are almost absolutely limited to the Milky 

 Way. Our information begins 134 years before Christ, and it ends 

 last year. The number of stars thus reported as new stars is thirty- 

 one, and of these only three have been seen outside the Milky Way. 

 Fig. 40 shows what the facts are with regard to the new stars. The 

 bright-line stars being distinguished by dark wafers, the new stars are 

 shown by white wafers. We notice that where we get practically the 

 greatest number of dark wafers we get a considerable number of white 

 ones. That means that these new stars take their origin in the same 

 part of space as that occupied by the bright-line stars, and it is also 

 interesting to point put that the void indicated where the Milky Way 

 is single, where there were no bright-line stars, is equally true for the 

 new stars; only one new star has been recorded in this region 

 (Fig. 41). 



As I have said, a great deal of interest has been attached by many 

 people to the question of the new stars, for the reason that whenever a 

 new star appeared in a part of the heavens where no star was seen 

 before, it was imagined that something miraculous and wonderful had 

 happened. That was justifiable while we were ignorant, but recent 

 work has shown, I think almost to a certainty, that the real genesis of 

 a new star is simply this. We have near the Milky Way a great 

 number of nebulae, planetary or otherwise we have more planetary 

 nebulae near the Milky Way than in any other part of the heavens ; 

 the nebulous patches also observed in it may include streams of 

 meteorites rushing about under the influence of gravity ; the origin of 

 a new star is due to the circumstance that one of these unchronicled 

 nebulae suddenly finds itself invaded by one of these streams of meteor- 

 ites. There is a clash. These meteorites we know enter our own 

 atmosphere at the rate of thirty-three miles a second, and we may 

 therefore be justified in assuming that any meteoritic stream in space, 

 even in the Milky Way, would not be going very much more slowly. 

 If we get this rapidly-moving stream passing through a nebula, which 

 is supposed to be a mass of meteorites more or less at rest, of course we 

 must get collisions ; of course, also, we shall get heat, and therefore 

 light. When the stream has passed through the nebula the luminosity 

 will dim and ultimately, attention having been called by this cataclysm 

 to that particular part of space, we shall find that there is a nebula 

 there. This has always been so ; and therefore in the case of new stars 

 we must always expect to get indications of the existence of two bodies, 

 the intruder and the body intruded upon. 



