﻿Trowbridge 
  and 
  Duane 
  — 
  Velocity 
  of 
  Electric 
  Waves. 
  297 
  

  

  we 
  possess 
  no 
  knowledge 
  why 
  carbon, 
  with 
  its 
  low 
  atomic 
  

   weight, 
  should 
  be 
  a 
  solid, 
  while 
  nitrogen 
  is 
  a 
  gas, 
  except 
  in 
  so 
  

   far 
  as 
  we 
  ascribe 
  molecular 
  complexity 
  to 
  the 
  former 
  and 
  com- 
  

   parative 
  molecular 
  simplicity 
  to 
  the 
  latter. 
  Argon, 
  with 
  its 
  

   comparatively 
  low 
  density 
  and 
  its 
  molecular 
  simplicity, 
  might 
  

   well 
  be 
  expected 
  to 
  rank 
  among 
  the 
  gases. 
  And 
  its 
  inertness, 
  

   which 
  has 
  suggested 
  its 
  name, 
  sufficiently 
  explains 
  why 
  it 
  has 
  

   not 
  previously 
  been 
  discovered 
  as 
  a 
  constituent 
  of 
  compound 
  

   bodies. 
  

  

  We 
  would 
  suggest 
  for 
  this 
  element, 
  assuming 
  provisionally 
  

   that 
  it 
  is 
  not 
  a 
  mixture, 
  the 
  symbol 
  A. 
  

  

  We 
  have 
  to 
  record 
  our 
  thanks 
  to 
  Messrs. 
  Gordon, 
  Kellas, 
  

   and 
  Matthews, 
  who 
  have 
  materially 
  assisted 
  us 
  in 
  the 
  prosecu- 
  

   tion 
  of 
  this 
  research. 
  

  

  Art. 
  XX 
  Y. 
  — 
  The 
  Velocity 
  of 
  Electric 
  Waves; 
  John 
  Trow- 
  

   bridge 
  and 
  William 
  Duane. 
  

  

  Sometime 
  since 
  the 
  following 
  method 
  of 
  measuring 
  the 
  

   velocity 
  of 
  electric 
  waves 
  suggested 
  itself 
  to 
  us 
  ; 
  increase 
  the 
  

   size, 
  and 
  if 
  necessary 
  change 
  the 
  shape 
  of 
  an 
  ordinary 
  Hertz 
  

   vibrator 
  until 
  the 
  period 
  of 
  oscillation 
  is 
  sufficiently 
  long 
  to 
  be 
  

   determined 
  by 
  photographing 
  the 
  spark 
  ; 
  measure 
  the 
  length 
  

   of 
  the 
  waves 
  induced 
  in 
  a 
  secondary 
  circuit 
  tuned 
  to 
  resonance 
  

   with 
  the 
  vibrator 
  ; 
  and 
  the 
  quotient 
  of 
  the 
  wave 
  length 
  by 
  

   the 
  time 
  of 
  a 
  complete 
  oscillation 
  will 
  be 
  the 
  required 
  velocity. 
  

  

  The 
  first 
  apparatus 
  experimented 
  with 
  was 
  that 
  used 
  by 
  Mr. 
  

   St. 
  John 
  in 
  investigating 
  the 
  peculiarities 
  of 
  waves 
  along 
  iron 
  

   wires. 
  For 
  a 
  detailed 
  description 
  of 
  this 
  apparatus 
  see 
  this 
  

   Journal 
  for 
  October, 
  1891. 
  It 
  has 
  been 
  assumed 
  by 
  certain 
  

   writers 
  that 
  the 
  reaction 
  between 
  the 
  circuits, 
  arranged 
  in 
  the 
  

   manner 
  employed 
  by 
  Mr. 
  St. 
  John, 
  is 
  to 
  a 
  large 
  extent, 
  what 
  

   would 
  be 
  called 
  in 
  the 
  older 
  theory 
  of 
  electricity, 
  electro-mag- 
  

   netic 
  rather 
  than 
  electrostatic. 
  Certain 
  phenomena, 
  however, 
  

   that 
  appeared 
  in 
  the 
  early 
  part 
  of 
  our 
  investigation 
  seemed 
  to 
  

   point 
  to 
  the 
  view 
  that 
  the 
  greater 
  portion 
  of 
  the 
  action 
  was 
  

   electrostatic 
  ; 
  and 
  we 
  therefore 
  concluded 
  to 
  arrange 
  the 
  

   apparatus 
  so 
  that 
  the 
  reaction 
  should 
  be 
  wholly 
  electrostatic, 
  

   thinking 
  by 
  this 
  means 
  to 
  obtain 
  a 
  more 
  powerful 
  oscillation 
  

   and 
  a 
  more 
  regular 
  wave 
  than 
  with 
  the 
  apparatus 
  described 
  

   and 
  used 
  so 
  successfully 
  by 
  Blond 
  lot. 
  The 
  first 
  attempt 
  

   arranged 
  on 
  the 
  electrostatic 
  principle 
  proved 
  a 
  complete 
  fail- 
  

   ure. 
  A 
  second 
  trial 
  about 
  a 
  fortnight 
  later, 
  however, 
  proved 
  so 
  

   successful 
  that 
  we 
  fully 
  determined 
  to 
  adopt 
  the 
  electrostatic 
  

   method. 
  

  

  Am. 
  Jour. 
  Sol— 
  Third 
  Series, 
  Vol. 
  XLIX, 
  No. 
  292.— 
  April, 
  1895. 
  

   20 
  

  

  