314 F. B. Taylor — Delerminate Orbital Stability. 



still narrower, too narrow probably for the capture of a 

 satellite, the normal eccentricity of newly captured bodies 

 being too great to be held in so narrow a space. Venus 

 could probably hold a well settled satellite if the high 

 eccentricity of the early stages of capture could be 

 avoided. Mercury presents a paradox, for the limits of 

 its satellite zone probably pass each other, the outer limit 

 being inside of the inner limit ; so it can have no satellite. 

 Space forbids any discussion here of the significance 

 of the other great features of the Planetary system — 

 the giant planets, the planetoid ring, Saturn's rings, 

 axial rotation, the meaning of the order of these features 

 in the system, and the simple way in which all of them 

 unite in confirming the theory of the growth of the system 

 by vortex capture and orbital expansion. But it is not 

 necessary to dwell further on these things here, for in 

 other Avritings I have already discussed all of them, the 

 most extended discussion being in the small volume 

 referred to above, entitled ' ' The Planetary System. ' '"^ 



Fort Wayne, IiuL, December 28, 1920. 



**'The Planetary System: A Study of Its Structure and Growth." T'ul)- 

 lished by the author at Fort Wayne, lud., and by C. D. Cazenove & Son, 

 London, in 1903 ; 268 pages. The discussion of determinate stability is 

 presented in more succinct form and probably more clearly in the present 

 paper, but the laws of satellite systems, and the process of their growth are 

 more fully set forth in Part I of the book. The application of the principle 

 of determinate stability in explanation of the great features and character- 

 istics of the Planetary system are more fully set out in Part II of the book 

 than elsewhere. Many things are presented which are necessarily omitted 

 from the present paper, and some of them give strong support to the present 

 hypothesis. A pamphlet of 40 pages epitomizing the same theme was printed 

 privately in 1898 under the title, ''An Endogenous Planetary System." 

 This was a sort of caveat on the idea, and only a few copies were sent out. 

 An earlier attempt at printing was made in 1891, when 144 pages were 

 printed. But this effort was premature, and the printing was never com- 

 pleted. In all of these papers, the subject was treated by the synthetic or 

 deductive method. In another paper prepared recently, under the title 

 ' ' The Growth of the Planetary System as Revealed in Its Vestiges, ' ' I have 

 endeavored to interpret the features by the analytic or inductive method. 

 By a study of the significance and relations of the facts alone, an effort is 

 made to discover by what process the system has grown. Preconceived 

 theories are avoided as far as possible. No mention is made of determinate 

 stability, except for the purpose of reference in a footnote at the end of the 

 paper. 



