﻿38 
  MR, 
  H. 
  T. 
  BROWS' 
  OX 
  THE 
  PERMIAN 
  

  

  diorite 
  (?), 
  differing 
  only 
  varietally 
  from 
  Xo. 
  2. 
  There 
  appear, 
  

   however, 
  in 
  this 
  case 
  to 
  have 
  been 
  two 
  varieties 
  of 
  pyroxene, 
  but 
  

   there 
  is 
  not 
  much 
  of 
  the 
  pale-green 
  " 
  viridite," 
  the 
  iron-stained 
  con- 
  

   stituents 
  predominating. 
  The 
  possibility 
  of 
  the 
  latter 
  having 
  been 
  

   hornblende 
  is 
  suggested 
  by 
  the 
  appearance 
  of 
  one 
  or 
  two 
  grains. 
  

  

  4. 
  Bosivortli 
  Wharf 
  Boring. 
  Depth 
  774 
  feet. 
  — 
  The 
  core 
  from 
  which 
  

   this 
  slice 
  has 
  been 
  cut 
  exhibits 
  two 
  distinct 
  colours 
  of 
  rock, 
  the 
  one 
  

   being 
  of 
  brownish 
  red 
  and 
  the 
  other 
  of 
  a 
  greenish 
  tint. 
  The 
  line 
  

   of 
  separation 
  between 
  the 
  two 
  is 
  a 
  crack, 
  which 
  has 
  been 
  filled 
  with 
  

   crystalline 
  dolomite. 
  

  

  Microscopically, 
  the 
  rock 
  resembles 
  Xos. 
  2 
  and 
  3, 
  but 
  is 
  less 
  

   coarsely 
  crystalline. 
  Some 
  of 
  the 
  pyroxenic 
  constituents 
  suggest 
  

   the 
  former 
  presence 
  of 
  hornblende. 
  The 
  brown 
  and 
  greenish 
  rocks 
  

   have 
  the 
  same 
  general 
  appearance. 
  

  

  These 
  rocks 
  are 
  all 
  in 
  a 
  very 
  decomposed 
  condition. 
  Professor 
  

   Bonney 
  informs 
  me 
  that 
  they 
  certainly 
  do 
  not 
  appear 
  to 
  belong 
  

   to 
  the 
  Charnwood 
  or 
  Xarborough 
  type, 
  nor 
  even 
  to 
  Barrow 
  Hill, 
  but 
  

   that 
  apparently 
  they 
  have 
  some 
  relation 
  to 
  the 
  Warwickshire 
  

   diorites. 
  It 
  is 
  difficult 
  to 
  decide, 
  however, 
  whether 
  the 
  Bosworth 
  

   rock 
  is 
  a 
  diabase 
  or 
  a 
  lahrador-dioriie 
  ; 
  but, 
  on 
  the 
  whole, 
  there 
  

   is 
  a 
  probability 
  that 
  the 
  principal 
  pyroxene 
  constituent 
  was 
  a 
  horn- 
  

   blende. 
  

  

  Mr. 
  T. 
  H. 
  Waller, 
  after 
  a 
  careful 
  comparison 
  of 
  these 
  slices 
  with 
  

   his 
  extensive 
  collection 
  of 
  the 
  "Warwickshire 
  diorites, 
  informs 
  me 
  

   that 
  the 
  Market 
  Bosworth 
  specimens 
  appear 
  to 
  be 
  very 
  similar 
  to 
  

   the 
  diorites 
  which 
  occur 
  in 
  sheets 
  in 
  the 
  Hartshill 
  rocks 
  of 
  the 
  

   Nuneaton 
  district, 
  but 
  that 
  from 
  their 
  decomposed 
  state 
  it 
  is 
  impos- 
  

   sible 
  to 
  speak 
  with 
  absolute 
  certainty 
  on 
  this 
  point. 
  

  

  EXPLANATION 
  OF 
  PLATE 
  I. 
  

  

  This 
  Plate 
  represents 
  the 
  section 
  in 
  the 
  open-work 
  at 
  Swadlincote 
  as 
  it 
  appeared 
  

   in 
  March 
  1888. 
  The 
  Bunter 
  Conglomerate 
  and 
  Lower 
  Keuper 
  Sandstone 
  

   and 
  Marls 
  rest, 
  almost 
  horizontally, 
  upon 
  highly 
  inclined 
  Permian 
  rocks, 
  

   which 
  are 
  in 
  turn 
  unconformably 
  underlain 
  by 
  Coal-measure 
  Clays 
  con- 
  

   taining 
  Coal-seams. 
  

  

  Discussiox. 
  

  

  The 
  President 
  referred 
  to 
  the 
  derivation 
  of 
  the 
  materials 
  of 
  the 
  

   Permian 
  breccia 
  as 
  an 
  important 
  instance 
  of 
  results 
  due 
  to 
  investi- 
  

   gation 
  by 
  local 
  students, 
  and 
  the 
  light 
  thereby 
  thrown 
  on 
  ancient 
  

   physiography. 
  He 
  was 
  sceptical 
  as 
  to 
  the 
  lacustrine 
  origin 
  of 
  these 
  

   breccias. 
  Why 
  not 
  subaerial, 
  like 
  those 
  in 
  the 
  interior 
  of 
  Asia 
  ? 
  — 
  

   subangnlar 
  masses, 
  transported 
  by 
  rainwash 
  to 
  a 
  distance 
  of 
  10 
  or 
  

   12 
  miles. 
  He 
  spoke 
  of 
  the 
  value 
  of 
  the 
  hand-borer, 
  and 
  referred 
  to 
  

   the 
  specimens 
  exhibited 
  at 
  the 
  Geological 
  congress. 
  

  

  Prof. 
  Boxxet 
  had 
  accompanied 
  the 
  Author 
  occasionally, 
  and 
  

   spoke 
  of 
  the 
  paper 
  as 
  the 
  cream 
  of 
  a 
  series 
  of 
  observations, 
  such 
  as 
  

   could 
  only 
  be 
  carried 
  out 
  by 
  one 
  living 
  in 
  the 
  district. 
  It 
  was 
  full 
  

   of 
  interesting 
  considerations. 
  He 
  agreed 
  as 
  to 
  the 
  existence 
  of 
  a 
  

   barrier 
  of 
  land 
  linking 
  the 
  old 
  area 
  of 
  Warwickshire 
  with 
  Charn- 
  

  

  