﻿Disintegration of Elements by a Particles. 



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between two steel plates in an atmosphere of carbon dioxide. 

 No evidence was found of any particles of range greater than 

 30 cm. Owing to hydrogen contamination of the Li and 

 Li 2 the observations at smaller ranges were not decisive. 

 Observations in the backward direction revealed no detectable 

 number of particles of range greater than 14 cm. 



Beryllium was examined as the powdered oxide, and there 

 was again no evidence of the emission of particles of longer 

 range than 30 cm. in the forward direction or 15 cm. in the 

 backward. 



Magnesium was examined with a sheet of the metal and 

 also with a screen of powdered magnesium. There was no 

 evidence of long-range particles. 



For silicon a screen of powdered silicon and a thin sheet 

 of quartz were used. With the sheet of quartz it was 

 possible to make observations in the forward direction at 

 absorptions as low as 17 cm. The scintillations observed 

 were due entirely to the natural H particles. 



To CO, 



Chlorine had been previously examined in the form of 

 various chlorides. These observations were repeated, and the 

 results confirmed the conclusion that particles of greater 

 range than 30 cm. were not liberated in any detectable 

 amount. In order to pursue the observations within the 

 range of free H particles a special series of experiments was 



