Variation of the Star C.P.I). - 41°'4511. 39 



These three equations are : — 



(1) Cos(/> - 3-077 VI - 0-991 Cos- (0135T)° 



(2) L = 1 - O-274(2 0-sin2^>) 



(3) Mag. = 2-5 (10 - Log L) + 10-Oom. 



In Fig. (1) is given the Hght curve of C.P.D. - 45^-4511 as deter- 

 xnined from observation. The thick dotted hne represents the 

 mean observed hght curve. 



In the same Figure the theoretical hght curve as determined from 

 ■equations (1), (2), and (3), is indicated by a fine dotted hne. 



The two hght curves are practicahy identical. This accordance 

 between theory and observation is remarkable. It is testimony to 

 the validity and accuracy of the conclusions come to as explanatory 

 of the star's variation. 



It is also, I think, strong presumptive evidence against the meteoric 

 theory of stellar variation — at least as an explanation of the variation 

 of C.P.D. - 41°-4511. 



The value of the density obtained also bears directly on this 

 question. 



It is true that the density of C.P.D. - 41°-4511 is considerably 

 greater than the mean density of stars of this type or class. In the 

 Astroi^hysical Journal, vol. x., No. 5, I pointed out that the average 

 -density of close binary stars is — 



0-13. 



A more recent investigation (not yet quite completed) based on 

 my own observations of eight southern Algol stars confirms this 

 value. 



In the case of C.P.D. — 41°-4511 we have a value of the density 

 ■equal to three times this mean value, and the pertinent question 

 .arises, Is it possible to have a globular mass of meteors, the density 

 of which is — 



0-4 



or one-half that of the sun ? 



It is possible if the meteors be solid bodies, of the specific gravity 

 of iron, and each meteor separated from its fellow by less than its 

 own diameter; but under no other conditions. Against this assump- 

 tion we postulate a luminous body revolving on its axis in less than 

 two days, and consequently subjected to great tidal stress and 

 ■strain. 



In a boundless universe there are no doubt boundless possibilities 

 of structural divergence ; but in our explanation of such phenomena 



