PROBLEMS OF INORGANIC CHEMISTRY. 45 



bodies. Xeedless to say, neither of the samples of glass contained 

 lead. 



I have mentioned these experiments in detail, because I think they 

 suggest wholly new lines of investigation. It would appear that if 

 energy can be poured into a definite chemical matter, such as glass, 

 it undergoes some change, and gives rise to bodies capable of being 

 tested for; I imagine that radio-active forms of matter are produced, 

 either identical with or allied to, those at present known. And just 

 as radium and other radio-active elements suffer degradation sponta- 

 neously, evolving energy, so I venture to think that if energy be con- 

 centrated in the molecules of ordinary forms of matter, a sort of poly- 

 merization is the result, and radio-active elements, probably elements 

 with high atomic weight, and themselves unstable, are formed. Of 

 course further research may greatly modify these views; but some 

 guide is necessary, and Mr. Ternent Cook, who has helped me in these 

 experiments, and I suggest this hypothesis (in the words of Dr. John- 

 stone Stoney, a hypothesis is ' a supposition which we hope ma} r be 

 useful ') to serve as a guide for future endeavor. 



In the light of such facts, speculation on the periodic arrangement 

 of the elements is surely premature. It is open to any one to make 

 suggestions; they are self-evident. Most of you will agree with the 

 saying ' it is easy to prophesy after the event.' I prefer to wait until 

 prophecy becomes easy. 



I must ask your indulgence for having merely selected a few out 

 of the many possible views as regards the Problems of Inorganic 

 Chemistry. I can only plead in excuse that my task is not an easy 

 one ; and I venture to express the hope that some light has been thrown 

 on the shady paths which penetrate that dark region which we term 

 the future. 



