﻿Chemistry 
  and 
  Physics. 
  463 
  

  

  SCIEl^TIFIC 
  INTELLIGENCE. 
  

  

  I. 
  Chemistry 
  and 
  Physics. 
  

  

  1. 
  Existence 
  of 
  masses 
  smaller 
  than 
  atoms. 
  — 
  At 
  the 
  late 
  meet- 
  

   ing 
  of 
  the 
  British 
  Association 
  at 
  Dover, 
  Prof. 
  J. 
  J. 
  Thomson 
  

   read 
  an 
  important 
  paper 
  on 
  this 
  subject. 
  He 
  considers 
  that 
  elec- 
  

   trification 
  consists 
  in 
  the 
  removal 
  from 
  the 
  atom 
  of 
  a 
  small 
  cor- 
  

   puscle 
  with 
  which 
  the 
  negative 
  charge 
  is 
  associated. 
  The 
  

   remaining 
  large 
  portion 
  of 
  the 
  mass 
  is 
  positively 
  charged. 
  This 
  

   view 
  is 
  supported 
  by 
  Prout's 
  hypothesis 
  that 
  the 
  mass 
  of 
  an 
  atom 
  

   is 
  not 
  invariable 
  and 
  by 
  the 
  evidence 
  derived 
  by 
  Lockyer 
  and 
  

   others 
  from 
  spectroscopic 
  observations. 
  — 
  Nature, 
  Oct. 
  12, 
  1899. 
  

  

  J. 
  T. 
  

  

  2. 
  Dispersion 
  of 
  the 
  Cathode 
  Hays 
  by 
  magnetic 
  force. 
  — 
  M. 
  

   BiRKELAND 
  lias 
  obscrvcd 
  that 
  when 
  a 
  narrow 
  beam 
  of 
  cathode 
  

   rays 
  produced 
  by 
  an 
  induction 
  coil 
  is 
  deflected 
  by 
  a 
  magnetic 
  

   field, 
  that 
  certain 
  rays 
  are 
  deflected 
  more 
  than 
  others, 
  and 
  he 
  has 
  

   given 
  to 
  this 
  eff^ect 
  the 
  name 
  of 
  the 
  magnetic 
  spectrum. 
  R. 
  

   J. 
  Strutt 
  of 
  Trinity 
  College, 
  Cambridge, 
  has 
  examined 
  this 
  

   subject 
  and 
  by 
  the 
  use 
  of 
  a 
  storage 
  battery 
  of 
  800 
  cells 
  shows 
  

   that 
  the 
  formation 
  of 
  the 
  magnetic 
  spectrum 
  is 
  due 
  to 
  a 
  pecu- 
  

   liarity 
  of 
  the 
  induction 
  coil. 
  The 
  cathode 
  rays 
  produced 
  by 
  a 
  

   battery 
  are 
  homogeneous. 
  — 
  Phil. 
  Mag., 
  Nov., 
  1899, 
  pp. 
  478-480. 
  

  

  J. 
  T. 
  

  

  3. 
  A 
  neio 
  Padio-active 
  Substance. 
  — 
  M. 
  A. 
  Debierne 
  has 
  iso- 
  

   lated 
  from 
  pitchblende 
  a 
  substance 
  which 
  emits 
  rays 
  which 
  are 
  

   100,000 
  times 
  stronger 
  than 
  those 
  given 
  ofl* 
  by 
  uranium. 
  They 
  

   render 
  gases 
  capable 
  of 
  discharging 
  electricity, 
  excite 
  the 
  phos- 
  

   phorescence 
  of 
  barium 
  platino-cyanide 
  and 
  affect 
  photographic 
  

   plates. 
  — 
  Conqjtes 
  Rendiis, 
  Oct. 
  16. 
  j. 
  t. 
  

  

  4. 
  Radio-active 
  effect 
  of 
  Barium 
  Salts 
  and 
  Polonium. 
  — 
  In 
  the 
  

   course 
  of 
  a 
  paper 
  on 
  these 
  subjects, 
  F. 
  Giesel, 
  the 
  author, 
  states 
  that 
  

   a 
  surprising 
  difference 
  exists 
  in 
  regard 
  to 
  the 
  penetrating 
  power 
  of 
  

   the 
  rays 
  of 
  radium 
  and 
  those 
  of 
  polonium. 
  While 
  the 
  rays 
  from 
  

   radium 
  penetrate 
  fairly 
  well 
  a 
  silver 
  thaler, 
  the 
  rays 
  from 
  

   polonium, 
  although 
  more 
  intense, 
  are 
  absorbed 
  by 
  thinner 
  metallic 
  

   plates. 
  The 
  shadow 
  of 
  the 
  hand 
  and 
  of 
  metallic 
  objects 
  thrown 
  

   by 
  the 
  polonium 
  rays 
  on 
  a 
  fluorescent 
  screen 
  are 
  stronger 
  in 
  con- 
  

   trast 
  than 
  when 
  produced 
  by 
  the 
  radium 
  rays. 
  — 
  Wied. 
  Ann., 
  

   No. 
  9, 
  1899, 
  pp. 
  91-94. 
  " 
  " 
  j. 
  t. 
  

  

  5. 
  Becquerel 
  rays. 
  — 
  These 
  rays 
  seem 
  to 
  be 
  Rontgen 
  rays 
  of 
  

   feeble 
  intensity 
  ; 
  in 
  common 
  with 
  them 
  they 
  act 
  upon 
  photographic 
  

   plates, 
  dissipate 
  electric 
  charges, 
  and 
  produce 
  luminescence. 
  The 
  

   intensity 
  of 
  the 
  rays 
  appears 
  to 
  be 
  kept 
  up 
  without 
  apparent 
  con- 
  

   sumption 
  of 
  energy. 
  J. 
  Elster 
  and 
  H. 
  Geitel 
  have 
  studied 
  

   the 
  behavior 
  of 
  these 
  rays, 
  which 
  were 
  produced 
  from 
  a 
  piece 
  of 
  

   Joachimsthal 
  pitchblende 
  of 
  300 
  grams 
  weight, 
  7^^^^ 
  long, 
  ^^^ 
  

   broad 
  and 
  1*5^™ 
  thick. 
  They 
  appear 
  to 
  be 
  uninfluenced 
  by 
  expo- 
  

  

  