Prof. P. E. Chase on the Nebular Hypothesis. 363 



angular velocity than the nebular nucleus, so that a planet might 

 revolve in less time than its sun rotated, or a satellite in less 

 time than its primary, until I called attention to the fact that 

 the time of nucleal rotation must vary as the f power of the 

 time of superficial nebular revolution. 



The significance of this relation does not seem, even now, to 

 be generally understood; for when Professor Hall found the 

 unprecedented rapidity with which the inner satellite of Mars 

 actually revolves, some thought that he must have made a 

 mistake in his calculations, and others assumed that the dis- 

 covery was fatal to the nebular hypothesis. It may therefore 

 be a fitting time for an explicit statement of some obvious evi- 

 dences of present nebular activity, such as are shown in the 

 following comparative synopsis: — 



M^- 



n 



n 2 



n*=S 2 =22 2 



7T 



ir?i=2 3 



™*=* 3 =2© 





7T 2 



7r%=6 3 =2h 3 



7T 2 W 2 = J 4 





7T* 



7r%=2e 2 



7T% 2 =0p o 





7r^?3=2$ 3 | 







M = present modulus of light at Sun's surface = 2204*95 

 x Earth's semiaxis major. I have already shown the im- 

 portance of this quantity, (1) by identifying the velocity of 

 light with the limiting velocity toward which the mean solar 

 centrifugal and centripetal forces both tend, (2) by showing 

 that the same harmonic progression is manifested in the Fraun- 

 hofer lines and in planetary distances, (3) by tracing numerous 

 harmonic arrangements among spectral lines of chemical ele- 

 ments. M is the common dividend for all the planetary posi- 

 tions; the combinations of various powers of it and n are 

 divisors. 



it = ratio of circumference to diameter, and also, as I have 

 shown, ratio of incipient to complete dissociative force. 

 2 



n= o__ 9 . 9 =11'65684*. I propose to call this quantity 



" Griimmere's criterion," because I obtained it by a calculation 

 which was first suggested by a criticism of Samuel J. Gum- 

 mere, late President of Haverford College. The criticism, 

 together with Ennis's rejoinder, may be found in Appendix II. 

 to ' Origin of the Stars.' 



* Phil. Mao-. October 1877. 



