578 



SCIENCE PROGRESS 



Element. 



Tungsten 



Cerium 



Lanthanum 



Barium 



Caesium 



Xenon 



Iodine 



Tellurium 



Antimony 



Tin . 



Indium 



Cadmium 



Silver 



Palladium 



Rhodium 



Ruthenium 



Molybdenum 

 Niobium . 

 Zirconium . 

 Yttrium 

 Strontium. 

 Rubidium . 

 Krypton . 

 Bromine . 



This table contains Blake and Duane's own results, 

 together with a result for tungsten, which is estimated from 

 Dershem's result as given in Table III. above. The figures 

 in the last column are calculated from the values of the 

 wave-lengths. Note their even increase with atomic number. 



Such frequencies are to be looked on as among the most 

 fundamental characteristics of the atoms. 



In a second direction, greater experimental accuracy has 

 made it possible to determine in a new way the radiation 

 constant h. 



From many converging lines of evidence it has for some 

 time been supposed that there are discontinuities in either 

 the emission or absorption of radiation or in both these pro- 

 cesses. According to certain theories energy of radiation of 

 a given frequency is transferred in multiples of a unit which 

 is equal to the frequency multiplied by the constant h ; 

 and not in any fractions of that unit. The idea is a funda- 



