THOUGHTS ON NATURAL PHILOSOPHY. 49 



starting with the hypothesis that the material atom 

 is solely composed of electric particles. His figures, 

 though also very high, are lower than those just 

 given. He finds that the energy accumulated in 

 one gramme of matter represents 1.02 x io 19 ergs, 

 which would be about 100,000,000,000 kilogram- 

 metres. These figures only represent, according to 

 him, " an exceedingly small fraction " of that 

 possessed by the atoms at the beginning and 

 gradually lost by radiation. 



Under what forms can intra-atomic energy exist, 

 and how can such colossal forces have been concen- 

 trated in very small particles ? The idea of such a 

 concentration seems at first sight inexplicable, because 

 our ordinary experience tells us that the extent of 

 mechanical power is always associated with the 

 dimensions of the apparatus concerned in its produc- 

 tion. A 1,000 h.p. engine is of considerable volume. 

 By association of ideas we are therefore led to believe 

 that the extent of mechanical energy implies the extent 

 of the apparatus which produces it. But this is a pure 

 illusion consequent on the weakness of our mechanical 

 systems, and easy to dispel by very simple calculations. 

 One of the most elementary formulas of dynamics 

 teaches us that the energy of a body of constant size 

 can be increased at will by simply increasing its speed. 

 It is therefore possible to imagine a theoretical 

 machine composed of the head of a pin turning 

 round in the bezel of a ring, which, notwithstanding 

 its smallness, should possess, thanks to its rotative 

 force, a mechanical power equal to that of several 

 thousands of locomotives. 



4 



