1896. J OUi [Leonardo 



conductive areas, and tlius supplying the conductor, the theory is 

 proved to be correct, for the x-rays and fluorescence are seemingly extin- 

 guished and we have established the short circuit in both tubes through 

 the medium of the Lenard rays and the aqueous vapor. 



The following conclusions may be drawn from these experiments : 



1 . From the fact that a short circuit may be established between the 

 cathodes in an induced electric field outside the tube, by placing an 

 electrical conductor in certain positions outside the tube, not occupied 

 by the Lenard rays, but occupied by the x-rays, we may conclude that 

 the Lenard rays are conductors of electricity, while the x-rays are not. 

 This would also account for the difl'erence in the action of magnetic 

 fields upon the cathode or Lenard rays and the x-rays, and, conversely, 

 that action would confirm the deduction regarding the conductivity and 

 non-conductivity of the two rays. 



This deduction is also compatible with the phenomena observed in the 

 discharge of electrified bodies by the x-ray, the ultra-violet rays, and 

 other forms of light rays. 



2. From the condition found to be present in tube A, that is, the 

 presence of an area which is a non-conductor of electricity and is free 

 from Lenard rays, and yet is the area of most intense x-rays, we may 

 conclude that the x-ray emanates from the surface of the reflector in 

 this type of tube, and is not due to the bombardment of the wall of the 

 tube by the cathode rays, as no cathode rays strike the wall of the tube 

 in the area from which we find the greatest fluorescence. 



Further, from the fact that the x-ray is a non-conductor and is not 

 influenced by a magnetic field, while the Lenard rays are conductors 

 and are infiueuced by magnetic fields, it would seem probable that 

 these two forms of radiant energy difli'er essentially in their character, 

 the x-ray presenting most of the phenomena chai'acteristic of light, 

 while the Lenard raj^s present the phenomena of radiant matter. 



3. From the difference in the rapidity of the action of the two tubes 

 on the sensitive film we may conclude, that the presence of Lenard 

 rays in an x-ray field interferes with the photographic action of the 

 x-ray : consequently a tube of the greatest efficiency would be one so 

 constructed, that the Lenard rays would be reflected entirely outside of 

 the most intense x-ray field. 



It would seem probable that the efficiency of the focus type of x-ray 

 tube is in a measure due to such a reflection of the Lenard rays, as many 

 of those working with the single cathode focus tube have found, that 

 the point of greatest intensity of the x-ray is not at the point where 

 rays of ordinary light would be reflected if they emanated from the 

 cathode, that is, the point to which the Lenard rays are reflected, but is 

 at a point perpendicular to the focal point of the cathode rays upon the 

 platinum reflector. 



