Ixxxii KANT'S UNIVERSAL NATURAL HISTORY 



While these and similar comparisons have brought 

 out more exactly the points of agreement and 

 difference between Kant and Laplace, the progress 

 of observational Astronomy has given rise to a 

 number of very serious, if not absolutely fatal, 

 objections to the plausible simplicity of Laplace's 

 hypothesis, which, however, leave Kant's theory 

 almost entirely unscathed. They are formulated 

 and ably discussed on Laplace's standpoint by 

 M. Wolf, whose discussion is summarily reproduced 

 by Mr. Gore, and we may merely quote them from 

 M. Wolf, without entering into his details. ' i The 

 formation of the rings, such as Laplace supposes 

 them, is impossible. 2 These rings could give birth 

 only to a multitude of very small planets which 

 would fill the whole extension of the primitive 

 Nebula, and not to large planets separated by void 

 intervals. 3 The planets born of these rings ought 

 to have a retrograde motion of rotation. 4 The 

 first satellite of Mars, and the inner rings of Saturn, 

 are nearer their planets, and turn more rapidly than 

 the hypothesis of Laplace allows. 5 The motions 

 of the satellites of Uranus and Neptune are retro- 

 grade, as are also very probably the rotations of 

 these planets.' These objections are undoubtedly 

 very strong, and they might be multiplied. M. Wolf 

 defends the hypothesis very ably from their ap- 

 plication, but even he admits that one of them is 

 ' capital,' and M. Faye was so impressed by another, 

 viz. : the inconsistency of the facts founded upon 



