﻿Chemistry 
  and 
  Physics. 
  65 
  

  

  Bogen 
  39-52 
  mit 
  figur 
  71-152. 
  Leipzig, 
  1899 
  (Engelmann). 
  — 
  An 
  

   additional 
  part 
  of 
  this 
  most 
  valuable 
  treatise 
  of 
  Ostwald 
  on 
  

   General 
  Chemistry. 
  g. 
  f. 
  b. 
  

  

  9. 
  Grundriss 
  der 
  Allgemeineii 
  Ghemie 
  ; 
  von 
  W. 
  Ostwald. 
  

   Dritte 
  umgearbeitete 
  Auflage. 
  8vo. 
  pp. 
  xvi, 
  549. 
  Leipzig, 
  1899 
  

   (Engelmann). 
  — 
  This 
  excellent 
  abridgment 
  of 
  Professor 
  Ostwald's 
  

   larger 
  work 
  has 
  proved 
  so 
  useful 
  to 
  the 
  chemical 
  student 
  that 
  a 
  

   third 
  edition 
  will 
  be 
  warmly 
  welcomed. 
  The 
  revision 
  has 
  been 
  

   thorough 
  and 
  considerable 
  new 
  matter 
  has 
  been 
  added, 
  g. 
  f. 
  b. 
  

  

  10. 
  Laboratory 
  Manual. 
  Experiments 
  to 
  illustrate 
  the 
  Ele- 
  

   mentary 
  Principles 
  of 
  Chemistry; 
  by 
  H. 
  W. 
  Hillyer, 
  Ph.D. 
  

   8vo, 
  pp. 
  vi, 
  200. 
  New 
  York, 
  1899 
  (The 
  Macmillan 
  Co.).— 
  This 
  

   book 
  is 
  designed 
  for 
  the 
  use 
  of 
  college 
  students 
  in 
  general 
  chem- 
  

   istry, 
  the 
  odd 
  pages 
  being 
  left 
  blank 
  for 
  notes. 
  Part 
  I 
  comprises 
  

   the 
  preparation 
  and 
  properties 
  of 
  the 
  elements 
  and 
  their 
  com- 
  

   pounds, 
  and 
  Part 
  II, 
  the 
  verification 
  of 
  quantitative 
  laws. 
  It 
  

   seems 
  to 
  have 
  been 
  carefully 
  compiled. 
  g. 
  f. 
  b. 
  

  

  11. 
  Strahlung 
  and 
  Temper 
  atnr 
  der 
  Sonne 
  ; 
  von 
  Dr. 
  J. 
  Schei- 
  

   ner, 
  Professor 
  der 
  Astrophysik 
  an 
  der 
  Universitat 
  Berlin. 
  8vo, 
  

   pp. 
  iv, 
  99. 
  Leipzig, 
  1899 
  (Engelmann). 
  — 
  A 
  valuable 
  contribution 
  

   to 
  the 
  solar 
  radiation 
  question, 
  giving 
  the 
  latest 
  results 
  of 
  the 
  best 
  

   observers. 
  In 
  an 
  appendix 
  the 
  diameter 
  of 
  the 
  sun 
  is 
  discussed. 
  

  

  G. 
  F. 
  B. 
  

  

  1 
  2. 
  Influence 
  of 
  small 
  impurities 
  on 
  the 
  spectrum 
  of 
  a 
  gas. 
  — 
  The 
  

   difficulties 
  in 
  obtaining 
  pure 
  gases 
  for 
  spectrum 
  analysis 
  are 
  well 
  

   known 
  to 
  physicists. 
  These 
  gases 
  are 
  necessarily 
  contained 
  in 
  

   glass 
  tubes 
  or 
  receptacles 
  : 
  and 
  the 
  varying 
  quality 
  and 
  condi- 
  

   tions 
  of 
  the 
  glass 
  affect 
  the 
  conditions 
  of 
  the 
  gases, 
  especially 
  

   when 
  powerful 
  electrical 
  discharges 
  are 
  employed. 
  The 
  prep- 
  

   aration 
  of 
  X-ray 
  tubes 
  has 
  brought 
  out 
  forcibly 
  the 
  necessity 
  

   of 
  heating 
  the 
  glass 
  receptacles 
  repeatedly, 
  and 
  also 
  subjecting 
  

   them 
  to 
  electrical 
  discharges 
  in 
  order 
  to 
  drive 
  off 
  the 
  adhering 
  

   layers 
  of 
  air. 
  It 
  is 
  probable 
  that 
  one 
  never 
  succeeds 
  in 
  freeing 
  

   the 
  glass 
  entirely 
  from 
  aqueous 
  vapor. 
  Indeed 
  grave 
  doubts 
  

   exist 
  whether 
  many 
  of 
  the 
  spectral 
  lines 
  attributed 
  to 
  a 
  gas 
  — 
  

   for 
  instance, 
  hydrogen 
  — 
  are 
  really 
  lines 
  of 
  the 
  pure 
  gas. 
  Mr. 
  P. 
  

   Lewis 
  has 
  investigated 
  the 
  influence 
  on 
  the 
  spectrum 
  of 
  hydrogen 
  

   and 
  other 
  gases 
  of 
  small 
  impurities. 
  The 
  gases 
  were 
  in 
  electrode- 
  

   less 
  tubes, 
  in 
  order 
  to 
  avoid 
  the 
  questions 
  of 
  the 
  absorption 
  of 
  the 
  

   gases 
  by 
  metals. 
  He 
  found 
  that 
  a 
  small 
  quantity 
  of 
  oxygen 
  in 
  

   hydrogen 
  increased 
  the 
  brilliancy 
  of 
  the 
  hydrogen 
  spectrum 
  — 
  

   the 
  mercury 
  vapor 
  spectrum 
  appeared 
  to 
  strongly 
  diminish 
  the 
  

   brilliancy 
  of 
  the 
  hydrogen 
  spectrum. 
  Mr. 
  Lewis 
  is 
  of 
  the 
  opinion 
  

   that 
  the 
  mixed 
  spectrum 
  of 
  hydrogen 
  — 
  the 
  white 
  spectrum 
  and 
  

   the 
  characteristic 
  line 
  spectrum 
  which 
  appears 
  strongly 
  when 
  a 
  

   Leyden 
  jar 
  is 
  used 
  — 
  is 
  a 
  real 
  hydrogen 
  spectrum. 
  In 
  electrode- 
  

   less 
  tubes 
  the 
  hydrogen 
  spectrum 
  is 
  brightest 
  at 
  about 
  3 
  mm 
  pres- 
  

   sure 
  ; 
  and 
  in 
  electrode 
  tubes 
  at 
  0'6 
  mm 
  . 
  In 
  a 
  pure 
  oxygen 
  atmos- 
  

   phere 
  the 
  spectrum 
  of 
  mercury 
  vapor 
  arising 
  from 
  the 
  pump 
  was 
  

   not 
  present 
  ; 
  a 
  small 
  trace 
  of 
  hydrogen 
  brought 
  out 
  the 
  green 
  

  

  Am. 
  Jour. 
  Sci.— 
  Fourth 
  Series, 
  Vol. 
  IX, 
  No. 
  49.— 
  January, 
  1900. 
  

  

  