﻿198 
  E. 
  E. 
  BEERY 
  AND 
  PROF. 
  T. 
  G. 
  BONNET 
  ON 
  

  

  (3) 
  Syenite 
  from 
  Garendon 
  Quarry*. 
  

   Si0 
  2 
  51-54 
  

  

  A 
  J 
  

  

  Fe 
  2°3lQi.7Q 
  26-83 
  

  

  A10 
  3178 
  4-95 
  

  

  P 
  2 
  5 
  ; 
  0-59 
  

  

  MnO 
  trace. 
  

  

  CaO 
  9-92 
  

  

  MgO 
  4-15 
  

  

  K 
  o 
  1-28 
  

  

  Na 
  2 
  2-11 
  

  

  Total 
  101-37 
  

  

  This 
  is 
  a 
  fairly 
  typical 
  specimen 
  of 
  the 
  " 
  northern 
  syenites." 
  While 
  

   leaving 
  these 
  still 
  classed 
  with 
  the 
  syenites 
  and 
  maintaining 
  their 
  

   petrological 
  relations 
  with 
  the 
  southern 
  group, 
  we 
  called 
  attention 
  

   to 
  their 
  apparently 
  more 
  basic 
  character 
  and 
  closer 
  relations 
  with 
  

   the 
  diorites. 
  This 
  conclusion, 
  formed 
  after 
  examination 
  with 
  the 
  

   microscope, 
  is 
  fully 
  confirmed 
  by 
  the 
  above 
  analysis. 
  The 
  amount 
  

   of 
  A1.,0 
  3 
  seems 
  exceptionally 
  low, 
  as 
  that 
  of 
  Ee 
  2 
  3 
  is 
  high. 
  The 
  

   author, 
  indeed, 
  informed 
  me 
  that 
  he 
  was 
  not 
  quite 
  satisfied 
  with 
  the 
  

   results 
  of 
  the 
  method 
  which 
  he 
  had 
  adopted 
  for 
  separating 
  the 
  one 
  

   from 
  the 
  other. 
  (T. 
  G. 
  B.) 
  

  

  (4) 
  Syenite 
  from 
  Hunoote 
  Quarry, 
  Croft 
  Hill. 
  

  

  SiO., 
  64-30 
  

  

  Fe 
  Al 
  22-64 
  ' 
  4 
  * 
  75 
  

  

  Al 
  a 
  8 
  / 
  ^-89 
  

  

  MnO 
  trace. 
  

  

  CaO 
  . 
  3-98 
  

  

  MgO 
  . 
  142 
  

  

  £ 
  2 
  3-37 
  

  

  Na 
  2 
  3-84 
  

  

  H 
  2 
  1-60 
  

  

  Total 
  100-85 
  

  

  The 
  rock 
  of 
  Croft 
  Hill 
  is 
  a 
  representative 
  of 
  the 
  dominant 
  type 
  

   in 
  the 
  outlying 
  district 
  in 
  the 
  vicinity 
  of 
  jSTarborough. 
  It 
  is 
  hardly 
  

   to 
  be 
  distinguished 
  from 
  that 
  of 
  Enderby, 
  in 
  the 
  N.E., 
  and 
  is 
  closely 
  

   allied 
  to 
  that 
  of 
  the 
  Sapcote 
  massif 
  on 
  the 
  S.W. 
  It 
  differs 
  some- 
  

   what 
  from 
  the 
  rock 
  of 
  Barrow 
  Hill, 
  to 
  the 
  west, 
  and 
  that 
  near 
  

   Narborough 
  village, 
  to 
  the 
  E.N.E. 
  We 
  remarked 
  upon 
  its 
  general 
  

   relations 
  to 
  the 
  finer 
  variety 
  of 
  the 
  southern 
  syenites 
  of 
  Charnwood, 
  

   perferring 
  to 
  connect 
  it 
  with 
  these 
  rather 
  than 
  with 
  the 
  Warwick- 
  

   shire 
  diorites. 
  This 
  is 
  borne 
  out 
  by 
  the 
  analysis, 
  though 
  the 
  differ- 
  

   ence 
  in 
  the 
  percentage 
  of 
  Si0 
  2 
  is 
  a 
  little 
  greater 
  than 
  we 
  should 
  

  

  * 
  This 
  rock 
  and 
  the 
  " 
  porphyroid" 
  of 
  Sharpley 
  (No. 
  5) 
  were 
  dried 
  before 
  the 
  

   analyses 
  were 
  made; 
  and 
  the 
  amount 
  of 
  water 
  present 
  was 
  not 
  determined. 
  \ 
  

  

  