CERTAIN HARMONIES OF THE SOLAR SYSTEM. 91 



But if every hypothesis be rejected, the relations exist as more or less consistent, 

 but yet as ultimate facts ; i. e. without any explanation ; while the hypothesis, or 

 rather theory, which has been discussed in these pages, seems, with a more or less 

 perfect applicability, to include and grasp the ivliole. 



ADDENDUM. 



Consistency 62fZ. In addition to what is already stated as a part of Consistency 

 56th, it may be noted, that the resulting rotation of Mars as determined by 

 Kirkwood's Analogy, (108), is not merely, in so far as may he, confirmatory 

 of the half-planet arrangement of the asteroid-mass exhibited in (60) ; but also 

 of the value of the mass itself, as determined in (46) : the appropriate fraction of 

 the mass entering into the computation of the time of rotation in question. 



Note (A). 

 On the Origin of Clusters and NeJndce. 



■ The application of similar principles to those involved in the Nebular Hypothesis 

 of Laplace, but on a larger scale, and with reference to a greater variety of circum- 

 stances, led the author of this paper to his own hypothesis of the Spheroidal Origin 

 of Clusters and Nehida;. ; which represents those groups and conglomerations as 

 being the derivations of spheroids (or of rings derived from spheroids, or of masses 

 of an ancient ring-like form) all rotating in a state of dynamical equilibrium, at 

 periods very remote. But, that the process of cooling brought about like phenomena 

 to those which the Laplace-hypothesis maintains to have taken place in the instance 

 of our sun ; viz. the same more rapid rotation, sometimes with a local increase of 

 actual velocity, sometimes with a diminution of the same; but always, on the whole, 

 with an increase of angular velocity, continued, however, until the centrifugal force 

 of rotation overmastered cohesion and gravitation, and, in place of an " abandoned" 

 equatorial ring, portions of the ruptured material were ejected; to be left behind 

 the others, in the direction opposite to that of the rotation — the material thus being 

 broken into elongated fragments, and they again into drops ; but every drop having 

 in it material sufficient to. form a condensed nebula, or in the end a star: the result 

 presenting appearances such as are visible in the very beautiful nebula H. 1173; 

 the spirals described and figured by the late Lord Kosse ; the projections from the 

 one end of the annular nebula in Lyra; and the teeth leaning hackward in the 

 globular cluster H. 1968, etc. etc. 



The expositions in the communication here referred to, occupy in all twenty-nine 

 (double-column) quarto pages of the 2d volume o^{Gonld's) Astronomical Journal, 



