aiay 15, 1874.] -L^*^^ [Chase. 



COSMICAL EVOLUTION. 



By Pi.isy Earle Chase, 



Professor of Physics in Haverford College. 



{Bead before the American PMlosopJiical Society, May 15, 1874.) 



We may reasonably assume, that natural laws which are the most 

 general and the most constant are also the oldest, and that increasing 

 specialization is an indication of increasing, and comparatively recent, 

 development. 



The relation of luminous undulation to gravity may, i)erhaps, be 

 most satisfactorily formulated in the following tei'ms : 



At any point in space, perihelion velocity in a parabolic orbit (or its 

 equivalent, the velocity communicated by infinite gravitating appulsion 

 to the same point) is a mean proportional, between the variable mean 

 velocity of tlie vector-radial oscillation due to solar rotation,* and the con- 

 stant velocity of light. In other words, if t" = time of solar rotation 

 under a volume of any assumed radius, r, 



4'' A 9,yA 



In ■ V^gr :: y'^gr : ® .-.g^--- 



Since this formula, with the modifications indicited by Thesis 31, f is 

 applicable to all possible orbital motions about the Sun, as well as 1 1 solar 

 rotation and solar motion in space, it seems to represent the most gene- 

 ral, and, therefore, the oldest physical law yet discovered. :|: 



Next in point of generality, appears to be the relationship of orbital 

 belts to the point, towards or about which every particle of our system 

 is perpetually oscillating or tending to oscillate, viz., the mean-peri- 

 helion centre of gravity of our binary star§ (Sun-Jupiter). The 

 "-series of multiples of the primary radius which is determined by that 

 centre, § fixes the major axis of solar revolution about the stellar centre 

 of gravity, decides the relative masses of the Jovian and Telluric 

 systems, || and groups the planets into pairs, the points of division corres- 

 ponding with such apsides of Mercury, Earth, and Saturn, as recent in- 

 vestigations have shown to be actually correlated, through mutual plan- 

 etary interaction. 



The next steps in the development of planetary order, were, perhaps, 

 the fixing of an outer limit to the system, at such distance that the 

 passage of a light-wave, from its linear centre of oscillation to the sun, 

 is synchronous with the time of planetary revolution at the Sun's sur- 

 face ;** the establishment of new centres of inertia at harmonic nodes ; 



* The Sun's volume being supposed to expand or contract, homogeneously, to the 

 given point. 

 t Proc. Amer. Philo. Soc, April 17, 1?74. 

 % n\^ "H'l IIN TI' D'HS.^ n3N"V Genesis, i. 3. 

 § xiii. 471, sqq. 

 II xiii. 240, (3). 

 ** xiii. 248, et ante. 



