STORING-UP OF " N RAYS 43 



The phenomena of the storing-up of " N " 

 rays, which are the object of the present note, 

 ought naturally to be compared with those of 

 phosphorescence ; yet they present a quite 

 distinct feature, as I intend to show shortly. 



On the Strengthening Action of a Beam of Light 

 on the Eyes, when the Beam is accompanied 

 by "N" Rays (November 23, 1903). 



While studying the storing-up of " N " rays 

 by different bodies, I had occasion to observe 

 an unexpected phenomenon. My eyes were 

 fixed on a small slip of paper, dimly lighted, 

 distant about i metre from me ; a brick, one of 

 whose faces had been sun-exposed, having been 

 brought near laterally to the luminous pencil, 

 with its sun-exposed face turned towards me, 

 and a few decimetres distant from my eyes, I 

 saw the slip assume a heightened glow ; when 

 the brick was removed, or when its non-exposed 

 face was turned towards me, the paper grew 



