BELFAST 



NATURAL HISTORY 

 AND PHILOSOPHICAL SOCIETY 



SESSION 1914-15- 



I2ih /a?mary, IQIS- 



Professor Lindsay, M.A., M.D., F.R.C.P., President, in the Chair. 



THE STRUCTURE OF THE ATOM. 

 By R. T. Beatty, Esq., M.A., D.Sc. 



{Abstract.) 



The idea that matter is not infinitely divisible but that it 

 ultimately consists of small particles which cannot be permanently 

 split up by human agency is now firmly established under the 

 name of the Atomic Theory. The credentials which the Theory 

 possesses are very strong and they are credentials collected during 

 the last hundred years by innumerable workers in many countries. 

 In previous centuries it is true the Atomic Theory was vaguely 

 shadowed forth from time to time; the philosophers of the 

 Athenian Empire made it a subject for inconclusive speculation. 

 Lucretius must have reflected deeply upon it. But these early 

 ideas were not fruitful : they were but bubbles on the stagnant 

 pond of scientific thought. The conception of experimental science 

 had not then arisen ; that mighty touchstone by which theories 

 must stand or fall. The wildest speculation could not be 

 contradicted as long as no decisive evidence existed for or 

 against it. 



Time passed on : the mystical atomic theories of Democritus 

 and Lucretius had but little influence on the growth of the infant 



