260 FROM NEBULA TO NEBULA 



places. He has just reversed the film. Having started 

 out with the avowed object of clearing up the mystery of 

 climatic revulsions, he has ended by only floundering 

 deeper into the bog out of which he volunteered to lead 

 us. 



THE THEORY OF ARRHENIUS 



The celebrated Director of the Physico- Chemical 

 Nobel Institute of Stockholm, Svante Arrhenius, has ex- 

 pounded his views on this subject of cosmology in a small 

 volume called Worlds in the Making. As Doctor Cham- 

 berlin's theory was conceived from the viewpoint of a 

 geologist, so is this one conceived from the viewpoint of 

 the astrophysicist and chemist. 



According to a recent doctrine, the molecules of mat- 

 ter are believed to be in constant motion. Usually these 

 are so closely associated that they are much subject to 

 collision, but in free space, where they seldom strike 

 against one another, they are supposed to travel in 

 straight lines at velocities varying with their kinds. 

 Such motions when less than the "parabolic velocity" do 

 not permit the escape of the given molecule, but when the 

 contrary is the case, the molecule, it is declared, will 

 never again return to the cosmic body from which it took 

 its flight. Building upon this uncertain base, Arrhenius 

 imagines these vagabond molecules to accumulate for- 

 tuitously in the dust nebulae which, as I have previously 

 explained, modern scientists assert to be borne out by 

 light and electrical repulsive forces. 



As the molecules of matter are fundamentally con- 

 strued to be perfectly elastic, Arrhenius makes no con- 

 structive use of their high velocities, but the dust par- 

 ticles he supposes to beat each other into a glow and in 

 this state to attach to themselves the various free mole- 

 cules with which they come in contact. Thus, he says, 

 are the comets and the nuclei of planets formed. 



The orbital motions of the planets he " explains " 

 thus (ibid., pp. 203, 204) : 



