﻿Chemistry 
  and 
  Physics. 
  385 
  

  

  metallic 
  lithium 
  remains 
  besides 
  a 
  blue 
  crystalline 
  compound 
  

   Li(NH2CB[3) 
  or 
  lithium 
  monomethylammonium, 
  the 
  NH^CHg 
  

   pressure 
  being 
  less 
  than 
  one 
  atmosphere. 
  — 
  G. 
  i?., 
  cxxvii, 
  685-693, 
  

   1898; 
  ib.^ 
  cxxviii, 
  26-30, 
  1899; 
  Zeitschr. 
  Phys. 
  Chem.^ 
  xxix, 
  738, 
  

   '747, 
  September, 
  1899. 
  g. 
  f. 
  b. 
  

  

  6. 
  Oil 
  the 
  Action 
  of 
  Potassamwionium 
  and 
  of 
  Sodammoninm 
  

   on 
  Sidphur, 
  Selenium 
  and 
  Tellurium. 
  — 
  The 
  action 
  of 
  the 
  metallic 
  

   ammoniums 
  upon 
  sulphur, 
  selenium 
  and 
  tellurium 
  has 
  been 
  studied 
  

   by 
  HuGOT. 
  The 
  apparatus 
  used 
  consisted 
  of 
  two 
  large 
  parallel 
  

   tubes 
  of 
  glass 
  united 
  by 
  a 
  smaller 
  tube 
  containing 
  glass 
  wool. 
  

   The 
  metal 
  and 
  the 
  metalloid 
  are 
  placed 
  in 
  one 
  branch 
  of 
  the 
  tube, 
  

   previously 
  filled 
  with 
  ammonia 
  gas. 
  The 
  two 
  branches 
  are 
  then 
  

   sealed 
  and 
  connected 
  with 
  a 
  reservoir 
  containing 
  the 
  liquid 
  am- 
  

   monia, 
  which 
  collects 
  in 
  one 
  of 
  these 
  branches. 
  The 
  alkali- 
  

   ammonium 
  dissolves 
  in 
  the 
  excess 
  of 
  liquid 
  giving 
  a 
  reddish-brown 
  

   solution, 
  which 
  reacts 
  upon 
  the 
  sulphur, 
  selenium 
  or 
  tellurium 
  

   present, 
  giving 
  rise 
  to 
  a 
  white 
  powder 
  insoluble 
  in 
  the 
  liquid 
  (if 
  

   the 
  metalloid 
  is 
  present 
  in 
  excess) 
  and 
  which 
  has 
  the 
  composition 
  

   Na^S, 
  Na.-jSe, 
  or 
  Na^Te, 
  formed 
  with 
  sodium 
  or 
  K^S, 
  KgSe 
  or 
  

   KjjTe, 
  when 
  potassium 
  is 
  used. 
  They 
  are 
  soluble 
  in 
  water 
  free 
  of 
  

   air 
  and 
  give 
  a 
  colorless 
  solution. 
  When, 
  however, 
  the 
  metalloid 
  

   is 
  in 
  excess, 
  the 
  mono-compound 
  which 
  is 
  first 
  formed 
  dissolves, 
  

   the 
  liquid 
  becomes 
  brown 
  or 
  violet 
  and 
  very 
  limpid. 
  On 
  evapo- 
  

   rating 
  it 
  at 
  —25°, 
  with 
  subsequent 
  lowering 
  of 
  pressure, 
  the 
  ex- 
  

   cess 
  of 
  ammonia 
  is 
  removed 
  and 
  a 
  brown 
  crystalline 
  mass 
  is 
  left 
  

   having 
  the 
  composition 
  Kj^e^ 
  or 
  Na^Se^ 
  for 
  selenium 
  and 
  similar 
  

   formulas 
  for 
  sulphur 
  and 
  tellurium. 
  These 
  substances 
  are 
  all 
  

   crystalline, 
  are 
  soluble 
  in 
  water 
  but 
  not 
  soluble 
  in 
  liquid 
  ammonia. 
  

   They 
  absorb 
  ammonia 
  gas.— 
  (7. 
  B., 
  cxxix, 
  299-302; 
  388-390, 
  

   July, 
  August, 
  1899. 
  g. 
  r. 
  b. 
  

  

  7. 
  A 
  Short 
  History 
  of 
  the 
  Progress 
  of 
  Scientific 
  Chemistry 
  in 
  

   our 
  own 
  times 
  ; 
  by 
  William 
  A. 
  Tilden, 
  F.R.S,, 
  Professor 
  of 
  

   Chemistry 
  in 
  the 
  Royal 
  College 
  of 
  Science, 
  London. 
  8vo, 
  pp. 
  

   X, 
  276. 
  New 
  York, 
  1899 
  (Longmans, 
  Green 
  & 
  Co.). 
  — 
  This 
  ex- 
  

   cellent 
  little 
  book 
  of 
  Professor 
  Tilden's 
  had 
  its 
  origin 
  in 
  a 
  course 
  

   of 
  lectures 
  to 
  working 
  men 
  such 
  as 
  the 
  professors 
  in 
  the 
  Royal 
  

   School 
  of 
  Mines 
  and 
  the 
  Royal 
  College 
  of 
  Science 
  have 
  delivered 
  

   annually 
  for 
  the 
  last 
  five 
  and 
  thirty 
  years. 
  Among 
  the 
  subjects 
  

   treated 
  in 
  its 
  ten 
  chapters 
  are 
  Matter 
  and 
  Energy, 
  the 
  Chemical 
  

   Elements, 
  Standardization 
  and 
  Classification 
  of 
  Atomic 
  Weights, 
  

   Origin 
  of 
  the 
  ideas 
  of 
  Valency, 
  Synthetical 
  and 
  Stereo-Chemis- 
  

   try 
  and 
  the 
  Liquefaction 
  of 
  Gases. 
  The 
  facts 
  have 
  been 
  care- 
  

   fully 
  selected 
  and 
  are 
  attractively 
  presented. 
  The 
  book 
  will 
  be 
  

   of 
  great 
  service 
  to 
  the 
  chemical 
  student 
  as 
  a 
  valuable 
  resume 
  of 
  

   the 
  recent 
  progress 
  of 
  Chemical 
  Science. 
  g. 
  f. 
  b. 
  

  

  8. 
  Refraction 
  of 
  the 
  X-rays. 
  — 
  A 
  renewed 
  interest 
  has 
  been 
  taken 
  

   in 
  this 
  subject. 
  It 
  seemed 
  to 
  H. 
  Haga 
  and 
  C. 
  H, 
  Wind, 
  that 
  the 
  

   investigations 
  of 
  Fomm, 
  Wied. 
  Ann., 
  lix, 
  p. 
  350, 
  1896, 
  appeared 
  to 
  

   open 
  a 
  way 
  for 
  the 
  determination 
  of 
  a 
  possible 
  refraction. 
  It 
  was 
  

   shown 
  by 
  P. 
  G. 
  Tiddens, 
  Beibl, 
  xxi, 
  p. 
  603, 
  1897, 
  that 
  the 
  Fomm 
  

  

  