On the Causes ivhic/i produce the Phenomena of Neic Stars. 443 



April 16, 1891. 

 Sir WILLIAM THOMSON, D.C.L., LL.D., President, in the Chair. 



The Presents received were laid on the table, and thanks ordered 

 for them. 



The following Papers were read : 



"On the Causes which produce the Phenomena of New 

 Stars." By J. NORMAN LOCKYER, F.R.S. Received 

 November 28, 1890. 



(Abstract.) 



In communications to the Society during the last four years, I 



lave produced evidence to show that many so-called stars are com- 

 )osed of swarms of meteorites, and are increasing their temperature. 

 Taking a normal case of an undisturbed swarm, 1 have shown, by 



leans of a " temperature curve," the spectra given by the same mass 

 )f meteorites in its evolution from a nebula to a condensed and nearly 



)ld body. In considering this question, the appearance of the so- 

 called " New Stars " was referred to, and it was suggested that such 

 ippearances might be due to the collision of meteor-swarms or 

 streams in space, an idea which I first put forward with regard to 



Tova Cygni in 1877. 

 It became obvious that a complete discussion of these phenomena 



rould afford a valuable test of the general hypothesis, for the reason 

 that such bodies, instead of going forward along the temperature 

 curve, should go back aa they cooled and became invisible. 



All the observations have, therefore, been brought together and 

 liscussed from this point of view, the investigation having special 



eference to the sequence of spectroscopic changes from the first 

 ippearance of a new star to its final disappearance. 

 The various theories which have been put forward since the appear- 



ice of the new star of 1572 are referred to in the paper, and these 

 ire followed by a general statement of the meteoritic theory of the 

 origin of new stars. The remaining part of the paper consists of a 

 letailed discussion of all the observations of new stare which have 



2en made, and the final result is a complete justification of the con- 

 clusion arrived at from the first survey that " new stars, whether 

 seen in connexion with nebulae or not, are produced by the clash of 



leteor-swarms." Some of the chief points may be referred to here. 



