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law of motion in a nebula proves they would move, on 

 the nebular theory. The satellites of Uranus and 

 Neptune alone revolve in a direction opposite to that of 

 the others; but the motions of those planets themselves 

 correspond with the theory. There is a sufficient ex- 

 planation of this anomaly; and the conclusion of astron- 

 omers is, that these satellites will revolve later on, in 

 the true direction. 



The satellites of Uranus revolve around the planet 

 in one plane, inclined 83 degrees to that of the ecliptic, 

 and in an opposite direction from the motion of the 

 planet in its orbit. The law of dynamics implies that 

 this means an excess of energy. the inner satellite 

 making a revolution in one and a half days, which 

 in the course of ages will be regulated, by gradually 

 lessening this angle of plane, and decreasing the 

 velocity. At first the angle will rise to 90 degrees, and 

 then continue on the other side until it reaches 180 

 degrees. This would bring the motion in the right 

 direction ; not by any change in the absolute direction 

 of movement of the satellite, but by lessening the 

 energy of the movement, and at the same time increas- 

 ing the angle of its plane to more than 90 degrees. This 

 will bring the motion that now appears to be in the 

 opposite direction into the same direction with that of 

 the planet, or from retrograde to direct motion. This 

 is, likely, what w^ll occur to the satellites of both 

 Uranus and Neptune. The latter are now only at an 

 angle of 35 degrees to the ecliptic, but it is supposed 

 that this plane will pass through movements parallel 

 to that of the satellites of Uranus 



"The movements of the satellites of Uranus and 

 Neptune do not disprove the nebular hypothesis. 

 Rather they illustrate the fact that the great evolution 



