2 WHAT IS LIFE 



the alchemists, believed that there was a materia 

 prima, a simple essence out of which all existing 

 substances were built. And this being the case 

 they held that there was no real reason why any 

 one substance might not be turned into any other, 

 no reason, for example, why lead should not be 

 transmuted into gold. Stripped of all its gorgeous 

 imagery, deprived of its Ked Dragon and the 

 other fanciful terms which it brought into its 

 nomenclature, this was the underlying theory which 

 dominated all the work of the alchemists. And 

 as time went on and new discoveries were made, 

 men laughed at the follies of the alchemists and 

 wondered that any persons could have been so 

 foolish as to imagine that there was really only one 

 kind of basal principle of which the things that are 

 were various and differing manifestations. 

 Chemical So we were taught that there were seventy odd 



chemical elements and thai each of these was a 

 simple and undecomposable substance incapable 

 of being split up or of being transmuted into any- 

 thing else but itself. And so the underlying theory 

 became and for long remained one which proclaimed 

 an essential and absolute difference between the 

 so-called chemical elements. 



lium Time rolled on, and but a few years ago M. 



and Mme. Curie discovered radium, and the ex- 

 traordinary facts of radio-activity began to be 



