456 Dr. F. H. Newman on Active Modifications of 



passed through them. Strutt * found that nitrogen drawn 

 from a discharge tube had active properties, and concluded 

 from his experiments that the modified form was atomic in 

 composition. Wendt f has sho n that a modified form of 

 hydrogen, probably consisting of H 3 , is produced when an 

 electric discharge passes through hydrogen at low pressures. 

 In both cases the active form is not due to the ions 

 produced. 



The radiations from radioactive bodies, and especially the 

 a. rays, produce marked chemical effects in many substances. 

 In general, the chemical actions produced resemble those 

 due to the silent electric discharge. In some cases complex 

 molecules are dissociated, in others more complex mole- 

 cules are built up. Thus ozone is produced from oxygen. 

 Carbon dioxide is transformed into carbon, carbon monoxide, 

 and oxygen. Carbon monoxide is decomposed with the 

 appearance of solid carbon and oxygen. Ammonia is 

 changed into nitrogen and hydrogen, and in all cases the 

 chemical action is proportional to the amount of radio- 

 active body present, showing that the transformation of each 

 atom of the radioactive body produces a definite chemical 

 effect. 



It would be expected that the effect of the rays from any 

 radioactive substance, more particularly the a rays, would 

 be similar to the electric discharge at low pressure. It 

 should be possible to produce the active forms of hydrogen 

 and nitrogen by the a rays. The object of the present work 

 was to " activate" these gases in this manner, and show by 

 the formation of chemical compounds that the modified 

 form of the gas is more active, chemically, than the ordinary 

 gas. 



2. Description of Apparatus. 



The apparatus used is shown in fig. 1. The gas was pre- 

 pared, and stored in a very pure condition in a reservoir 

 from which it could enter D. The latter was a known 

 volume (0'106 c.c.) enclosed between two taps. A was 

 the experimental bulb containing the radioactive substance — 

 an electrolytic deposit of polonium on the plate G. The 

 support of the plate was sealed through a glnss stopper. 

 The polonium could thus be removed while the bulb A was 

 ^eing cleaned after each experiment. The element used 

 was introduced by the side tube B. The whole of the 

 apparatus was evacuated by a Toepler pump. F and E were 



* Proc. Rov. Soc. lxxxv. (1911). 

 f Nat. Acad. Sci. Proc. v. (1919). 



