﻿186 
  

  

  Messrs. 
  Trowbridge 
  and 
  Burbank 
  on 
  

  

  The 
  first 
  tube 
  is 
  shown 
  in 
  fig. 
  1. 
  It 
  consisted 
  of 
  a 
  straight- 
  

   wire 
  tube 
  joined 
  to 
  an 
  ordinary 
  Crookes 
  tube 
  of 
  the 
  focus 
  

   pattern. 
  This 
  latter 
  tube 
  was 
  joined 
  to 
  the 
  straight-wire 
  

   tube 
  in 
  order 
  to 
  test 
  the 
  vacuum 
  in 
  the 
  latter, 
  and 
  to 
  be 
  sure 
  

  

  that 
  the 
  necessary 
  conditions 
  existed 
  for 
  the 
  production 
  of 
  the 
  

   #-rays. 
  When 
  the 
  terminals 
  of 
  the 
  straight- 
  wire 
  tube 
  were 
  

   connected 
  to 
  the 
  Plante 
  machine 
  and 
  the 
  latter 
  was 
  excited, 
  

   the 
  entire 
  tube 
  fluoresced 
  brilliantly. 
  This 
  fluorescence 
  was 
  

   especially 
  bright 
  in 
  the 
  connecting 
  tuba 
  between 
  the 
  straight- 
  

   wire 
  tube 
  and 
  the 
  Crookes 
  tube, 
  and 
  a 
  beam 
  of 
  light 
  passed 
  

   across 
  the 
  Crookes 
  tube 
  and 
  formed 
  a 
  fluorescent 
  spot 
  on 
  its 
  

   bulb. 
  

  

  