162 THE MECHANISM OF LIFE 



between the rounded particles of the second element, so that A \ 

 they possessed a rotatory motion as well as a translational one. ] 



The first matter made up the sun and stars that is, the cosmic 

 bodies that are hot and radiate; the second matter made up the ' 

 heavens that is, the atmosphere and cosmic space, which j 

 convey radiation ; and the third matter was that of the earth and 

 other planets, bodies that are cold and are becoming inert.; 

 By vortices in the first and second matters he tried to explain 

 (but with no more success than Kant and Laplace) the evolution 

 of solar systems, while by the motion of the spiral particles he] 

 sought to explain attraction. The particles of the second ele-j 

 ment correspond to our modern atoms (or molecules, as Clerk j 

 Maxwell calls them). To what do the fine particles of the first ; 

 element correspond in our cosmogony ? 



Fifty years ago we should have said that the universe was j 

 made up of atoms, of matter which here and there were aggre- j 

 gated to form stars and planets, comets, nebula, and meteoritic j 

 dust in short, cosmic bodies attracting each other with forces 

 depending on their masses and on the distances between them 

 and that these bodies filled only a most insignificant fraction of 

 empty space. But they attracted each other across this space, j 

 and heat and light and electro-magnetic radiation were trans- 

 mitted through it, so that it could not be empty. There was a 

 medium the ether of space and this conveyed the radiation, j 

 So much had to be postulated merely to explain things and give 

 us a " working hypothesis," but what was the nature of the 

 ether ? It was something that was perfectly elastic, a kind of ; 

 jelly, so to speak, across which energy could pass without dis- 

 sipation. It had to be continuous and dense that is, there \ 

 could be no interspaces in it such as there are even in the densest \ 

 kinds of gross matter, which, Sir Oliver Lodge tells us, has a 

 texture like gossamer compared with that of the ether. Now 

 the latter cannot be absolutely continuous and perfectly elastic 

 according to the modern theory of energy as formulated byJ 

 Planck, for if it were it would possess " infinite degrees of 

 freedom," and thus it would absorb all the energy in a system, 

 leaving none at all to the matter of the system, and that we, 

 cannot believe. So quite lately physics has come back again 

 to the notion of a discrete ether of space something which is 

 particulate, but which must nevertheless be continuous in some \ 

 way or other, how it is difficult indeed to see ! 



