208 LAY SERMONS, ESSAYS, AND REVIEWS. [XL 



scientific flesh desirable, I think the effect of the stream of cold 

 water which has steadily flowed over geological speculation 

 within these walls has been of doubtful beneficence. 



The sort of geological speculation to which I am now referring 

 (geological aetiology, in short) was created, as a science, by that 

 famous philosopher Immanuel Kant, when, in 1775, he wrote his 

 General Natural History and Theory of the Celestial Bodies ; 

 or an Attempt to account for the Constitution and the Mechanical 

 Origin of the Universe upon Newtonian principles.&quot; 1 



In this very remarkable but seemingly little-known treatise, 2 

 Kant expounds a complete cosmogony, in the shape of a theory 

 of the causes which have led to the development of the universe 

 from diffused atoms of matter endowed with simple attractive 

 and repulsive forces. 



&quot; Give me matter,&quot; says Kant, &quot; and I will build the world ; &quot; 

 and he proceeds to deduce from the simple data from which he 

 starts, a doctrine in all essential respects similar to the well- 

 known &quot; Nebular Hypothesis &quot; of Laplace. 3 He accounts for the 

 relation of the masses and the densities of the planets to their 

 distances from the sun, for the eccentricities of their orbits, for 

 their rotations, for their satellites, for the general agreement in 

 the direction of rotation among the celestial bodies, for Saturn s 

 ring, and for the zodiacal light. He finds in each system of 

 worlds, indications that the attractive force of the central mass 

 will eventually destroy its organization, by concentrating upon 

 itself the matter of the whole system ; but, as the result of this 

 concentration, he argues for the development of an amount of 

 heat which will dissipate the mass once more into a molecular 

 chaos such as that in which it began. 



Kant pictures to himself the universe as once an infinite 



1 Grant (&quot; History of Physical Astronomy,&quot; p. 574) makes but the briefest 

 reference to Kant. 



2 &quot; Allgemeine Naturgeschichte und Theorie des Himmels ; oder Versuch 

 von der Verfassung und dem mechanischen Ursprunge des ganzen Weltge- 

 biindes nach Newton schen Grundsatzen abgehandelt. KANT S Sdmmtliche 

 Werke, Bd. i. p. 207. 



3 Systeme du Monde, tome ii. chap. 6. 



