255 

 An Investigation of IS'-Rays. 



R. R. Ramsey aud W. ?. Haseman. 



This paper is an account of an attempt of the authors to repeat the 

 experiments of R. Blondlot in which he has discovered that there is an 

 invisible radiation given off from an Auer (Welsbach) burner. Nernst himp 

 and other sources. 



Blondlot was investigating the polarization of X-rays (Comptes Rendus, 

 Feb. 23, 1903) and using a feeble spark gap as a detector. He thought 

 he had discovered that the X-rays were polarized in certain planes. In 

 a few days (Comptes Rendus. March 23, 1903) he was convinced that 

 the effects were due to other rays than X-rays. In May of the same 

 year (Comptes Rendus, May 11. 1903) an article by Blondlot appeared, 

 entitled, "Rays from an Auer Burner." An ordinary Welsbach bin-ner 

 (Auer burner) was surrounded with an iron chimney in which a window 

 was cut and closed with an alumiLum sheet .1 mm. thick. The radiation 

 from this window was allowed to fall on the little spark gap and the 

 intensity of the light from the spark was seen to increase. By means 

 of a quartz lens Blondlot was able to detect four different wave lengths. 

 The intensity of the spark gap is found to have four maximums as it is 

 moved to and fro along the principal axis of the lens. 



A week later (Comptes Rendus, May 25. 1903) Blondlot published 

 an article in which he gave a list of various sources of N-rays and 

 several means of detecting them, the chief ways being the little spark 

 gap: a sheet of silver heated to a very dull redness by a little gas 

 flame; a small phosphorescent screen which has been feebly excited l)y 

 sunlight or other source. 



The intensity or l)rilliancy of these detectors was found to increase 

 when the radiation fails upon them. In this article Blondlot calls the 

 new rays N-rays, from the town of Nancy, his home. 



In a short time afterward Blondlot published an article in which he 

 found that a Nernst lamp with an aluminum window is a good source. 

 He also found that certain substances store up N-rays when they are 

 exposed to N-rays and give off the rays afterward. Among those that 

 store lip the rays are quartz, stones and brick. Wood, aluminum, paper, 



