90 THE LIMITATIONS OF SCIENCE 



each other's motion, and he spends much labor and 

 great ingenuity in describing the possible inclinations 

 of axes and directions of motion of such a system, 

 but not satisfactorily. 



The sun and stars, as they now are, were not created 

 contemporaneously with the vortices but were a gradual 

 growth from them. When more dust of attrition was 

 ground from the rotating matter of a vortex than was 

 sufficient to fill the interstices of this matter, it began 

 to flow toward the center and along the axis of the 

 vortex, gradually forming there a nucleus, ires subtil et 

 ires liquide; namely, a luminous star. According to 

 Descartes's idea, which in spite of his contempt for au- 

 thority he borrowed from Aristotle and the schoolmen, 

 these stellar masses, consisting of matter of the first 

 kind exclusively, are pure celestial fire, which is thus 

 an entity and of all things the most fluid and so vio- 

 lently agitated as to be able to disintegrate the most 

 solid bodies. Fire of itself does not need to be replen- 

 ished but only seems to need replenishment, because the 

 particles of a terrestrial fire are constantly flying 

 away and being dissipated, and so must be renewed by 

 others derived from the pores of gross combustible 

 bodies and of air; but in celestial fires there is no need 

 of external replenishment because the steady stream 

 of fire-substance, flowing of its own accord to the 

 center of the vortex, maintains a constant supply. 

 Alas, that the spectroscope should show us that our sun 



