﻿246 
  F. 
  W. 
  Clarke 
  and 
  E. 
  A. 
  Schneider 
  — 
  Constitution 
  of 
  

  

  MgOH. 
  Representing 
  this 
  by 
  the 
  symbol 
  R', 
  the 
  three 
  ver- 
  

   miculites 
  give 
  the 
  following 
  empirical 
  formulae 
  : 
  

  

  Hallite 
  - 
  R"' 
  304 
  R" 
  B68 
  R' 
  202 
  H 
  m0 
  (SiO 
  4 
  ) 
  592 
  O 
  43 
  e, 
  215 
  aq. 
  

  

  White 
  Lenni 
  R'" 
  268 
  R" 
  586 
  R' 
  158 
  H 
  808 
  (Si0 
  4 
  ) 
  614 
  269 
  , 
  504 
  aq. 
  

  

  Green 
  " 
  R'", 
  18 
  R" 
  M8 
  R' 
  164 
  H 
  9M 
  (SiO 
  4 
  ) 
  583 
  O 
  408 
  , 
  366 
  aq. 
  

  

  These 
  reduce 
  at 
  once, 
  subject 
  to 
  small 
  uncertainties 
  as 
  to 
  

   hygroscopic 
  water, 
  to 
  mixtures 
  of 
  molecules 
  of 
  the 
  hydro- 
  

   clintonite 
  and 
  hydro 
  phlogopite 
  types, 
  with 
  small 
  amounts 
  of 
  

   chloritic 
  compounds 
  Mg(Si0 
  4 
  ) 
  9 
  (MgOH) 
  6 
  and 
  Mg 
  2 
  (Si0 
  4 
  ),H 
  4 
  . 
  

   Upon 
  this 
  basis 
  the 
  three 
  minerals 
  become 
  : 
  

  

  Hallite 
  

  

  _.. 
  Al(Si0 
  4 
  ) 
  3 
  Mg 
  3 
  H 
  3 
  3 
  aq. 
  

  

  7 
  molecules. 
  

  

  

  A10 
  2 
  MgSi0 
  4 
  H 
  3 
  

  

  18 
  

  

  t 
  

  

  

  Mg(Si0 
  4 
  ) 
  2 
  (MgOH) 
  6 
  

  

  3 
  

  

  1 
  

  

  

  Mg 
  2 
  (Si0 
  4 
  ) 
  2 
  H 
  4 
  

  

  2 
  

  

  « 
  

  

  White 
  Lenni 
  

  

  ... 
  Al(SiOJ,Mg,H, 
  3 
  aq. 
  

  

  6 
  

  

  t 
  

  

  

  A10 
  2 
  MgSi0 
  4 
  H 
  

  

  5 
  

  

  ' 
  

  

  

  Mg(Si0 
  4 
  ) 
  2 
  (MgOH) 
  6 
  

  

  1 
  

  

  u 
  

  

  Green 
  Lenni 
  

  

  ... 
  Al(Si0 
  4 
  i 
  3 
  Mg 
  3 
  H 
  3 
  3 
  aq. 
  

  

  4 
  

  

  u 
  

  

  

  A10„MgSi0 
  4 
  H 
  3 
  

  

  8 
  

  

  a 
  

  

  

  Mg(Si0 
  4 
  ) 
  2 
  (MgOH) 
  6 
  

  

  1 
  

  

  le 
  

  

  The 
  actual 
  ratios 
  observed 
  were 
  slightly 
  more 
  complex, 
  but 
  

   the 
  foregoing 
  expressions 
  accord 
  well 
  with 
  the 
  analyses. 
  Here, 
  

   as 
  previously, 
  we 
  may 
  reduce 
  the 
  analyses 
  to 
  typical 
  form 
  and 
  

   100 
  per 
  cent, 
  reckoning 
  Fe 
  2 
  3 
  as 
  A1 
  2 
  3 
  , 
  etc. 
  The 
  comparison 
  

   is 
  as 
  follows 
  : 
  

  

  Analyses 
  reduced. 
  

  

  A 
  (Hallite). 
  B 
  (White). 
  D 
  (Green.) 
  

  

  Si0 
  2 
  36-93 
  37-56 
  36*33 
  

  

  A1 
  2 
  3 
  16-13 
  14-92 
  16-83 
  

  

  MgO 
  31-58 
  30-41 
  29-44 
  

  

  H 
  2 
  _. 
  11-34 
  8-86 
  10-26 
  

  

  Aq 
  4-02 
  9-25 
  6'84 
  

  

  100-00 
  100-00 
  100-00 
  

  

  MgO 
  in 
  MgOH 
  8-09 
  6'30 
  6'57 
  

  

  Calculated. 
  

  

  A. 
  B. 
  D. 
  

  

  Si0 
  2 
  36-47 
  38-11 
  36-61 
  

  

  A1 
  2 
  3 
  15-82 
  14-25 
  16'97 
  

  

  MgO.. 
  31-75 
  30-49 
  29-95 
  

  

  H 
  2 
  __ 
  11-27 
  8-92 
  10-47 
  

  

  Aq 
  4-69 
  8-23 
  6'00 
  

  

  100-00 
  100-00 
  100-00 
  

  

  MgO 
  in 
  MgOH... 
  8*93 
  6-10 
  6*66 
  

  

  