24 "N" RAYS 



On the Existence of Solar Radiations capable 

 of traversing Metals, Wood, etc. (June 15, 

 1903). 



I have recently proved that the majority of 

 artificial sources of light and heat emit radia- 

 tions which are able to traverse metals and a 

 great number of bodies, opaque in regard to the 

 spectral radiations hitherto known (see p. 18). 

 It was desirable to ascertain whether radiations 

 analogous to the former which, for brevity, I 

 call " N " rays are also emitted by the sun. 



As I have shown, " N " rays act on phos- 

 phorescent substances by heightening or stimu- 

 lating the pre-existing phosphorescence, an 

 action similar to that of red and infra-red rays 

 discovered by Edmond Becquerel (see p. 74). 

 I utilized this phenomenon to find out whether 

 the sun sends us " N " rays. 



A completely enclosed dark room has one 

 window exposed to the sun. This is shut by 

 interior, opaque panels of oak, 15 mms. thick. 

 Behind one of these panels, at any distance 

 i metre, for instance a thin glass tube is 



