﻿90 
  PROF. 
  T. 
  G. 
  BONNET 
  ON 
  TWO 
  TEA 
  VERSES 
  OF 
  THE 
  

  

  the 
  range. 
  These 
  rocks 
  have 
  a 
  marked 
  resemblance 
  to 
  the 
  " 
  Lepon- 
  

   tine 
  gneiss 
  " 
  of 
  the 
  Central 
  Alps. 
  I 
  wrote 
  in 
  my 
  diary 
  : 
  — 
  " 
  The 
  

   rocks 
  seen 
  at 
  the 
  head 
  of 
  the 
  Gschlossthal 
  vary 
  in 
  aspect 
  from 
  the 
  

   i 
  Antigorio 
  ' 
  gneiss 
  through 
  the 
  Monte 
  Leone 
  gneiss 
  to 
  that 
  of 
  the 
  

   pass 
  of 
  St. 
  Gothard, 
  but 
  I 
  have 
  seen 
  nothing 
  which 
  resembles 
  the 
  

   Tremola 
  schists." 
  

  

  The 
  strong-banded, 
  micaceous 
  and 
  hornblendic 
  gneisses 
  mentioned 
  

   above 
  are 
  traversed 
  on 
  the 
  ascent 
  to 
  the 
  Yelber-Tauern 
  pass. 
  My 
  

   observations 
  of 
  the 
  foliation, 
  which 
  is 
  often 
  associated 
  with 
  mineral 
  

   banding, 
  give 
  strikes 
  varying 
  from 
  E.N.E. 
  to 
  E.S.E., 
  with 
  a 
  moderate 
  

   dip, 
  say 
  about 
  25°, 
  on 
  the 
  southern 
  side 
  ; 
  but 
  there 
  are 
  frequent 
  

   indications 
  of 
  rolling 
  and 
  twisting, 
  for 
  higher 
  up 
  the 
  dips 
  vary 
  from 
  

   the 
  southern 
  to 
  the 
  northern 
  side, 
  and 
  north-westerly 
  strikes 
  seem 
  

   to 
  predominate. 
  As 
  we 
  approach 
  the 
  crest 
  of 
  the 
  pass 
  the 
  beds 
  are 
  

   more 
  coarsely 
  crystalline 
  and 
  may 
  be 
  true 
  granites 
  ; 
  they 
  show 
  a 
  

   certain 
  foliation, 
  but 
  not 
  mineral 
  banding. 
  On 
  the 
  upper 
  part 
  of 
  the 
  

   descent 
  towards 
  the 
  north 
  we 
  meet 
  with 
  a 
  considerable 
  amount 
  of 
  

   hornblendic 
  rock 
  (HornblendescMefer, 
  V. 
  II.), 
  sometimes 
  dark, 
  some- 
  

   times 
  spotted 
  with 
  white 
  felspar 
  (?), 
  occasionally 
  rather 
  coarse, 
  

   slightly 
  foliated 
  or 
  now 
  and 
  then 
  even 
  banded, 
  varying 
  from 
  massive 
  

   to 
  rather 
  platy 
  in 
  structure, 
  on 
  the 
  whole 
  very 
  like 
  some 
  of 
  the 
  horn- 
  

   blende-rock 
  in 
  the 
  Hebridean 
  series. 
  Very 
  much, 
  if 
  not 
  all, 
  may 
  be 
  

   modified 
  igneous 
  rock, 
  which 
  hypothesis 
  is 
  confirmed 
  by 
  the 
  outlines 
  

   of 
  the 
  outcrops 
  indicated 
  on 
  the 
  map. 
  Some 
  distance 
  from 
  the 
  top 
  of 
  

   the 
  pass 
  we 
  noticed 
  that, 
  in 
  the 
  crags 
  on 
  the 
  left 
  bank 
  of 
  the 
  upland 
  glen 
  

   which 
  we 
  were 
  descending, 
  masses 
  of 
  rock, 
  probably 
  from 
  50 
  feet 
  to 
  

   about 
  300 
  feet 
  thick, 
  exhibited 
  a 
  kind 
  of 
  stratification, 
  indicated 
  by 
  

   differences 
  of 
  tint, 
  and 
  these 
  dipped 
  clearly 
  northwards, 
  at 
  perhaps 
  an 
  

   average 
  angle 
  of 
  40°. 
  Beyond 
  this 
  the 
  bed 
  of 
  the 
  glen 
  is 
  interrupted 
  by 
  

   a 
  range 
  of 
  cliffs. 
  The 
  bottom 
  of 
  the 
  slope 
  is 
  reached 
  by 
  a 
  rapid 
  and 
  

   rough 
  descent 
  in 
  a 
  north-westerly 
  direction, 
  during 
  which 
  we 
  ob- 
  

   served 
  that 
  the 
  mica 
  now 
  and 
  then 
  became 
  more 
  silvery, 
  and 
  the 
  

   rock, 
  as 
  a 
  whole, 
  assumed 
  a 
  less 
  " 
  ancient 
  " 
  aspect. 
  On 
  reaching 
  the 
  

   bottom 
  the 
  scenery 
  changes, 
  the 
  stream 
  becoming 
  bordered 
  by 
  sloping 
  

   pastures 
  and 
  copses, 
  and 
  no 
  rock 
  was 
  seen 
  in 
  situ 
  till 
  after 
  passing 
  

   the 
  Pinzgauer 
  Tauernhaus 
  (3,5-30 
  feet), 
  when 
  a 
  rather 
  fissile 
  chloritic 
  

   schist 
  crops 
  out. 
  Hence 
  to 
  near 
  Mittersill 
  little 
  rock 
  is 
  seen, 
  what 
  

   there 
  is 
  being 
  either 
  the 
  normal 
  chloritic 
  schist 
  or 
  green 
  rock 
  of 
  a 
  

   not 
  very 
  definite 
  character. 
  The 
  lateral 
  torrents, 
  however, 
  bring 
  

   down 
  blocks 
  of 
  fine-grained 
  rather 
  banded 
  gneisses, 
  darker 
  and 
  

   lighter, 
  of 
  various 
  gneisses 
  and 
  schists 
  approaching 
  the 
  Lepontine 
  

   type, 
  with 
  some 
  which 
  appear 
  to 
  belong 
  to 
  the 
  "Thonglimmerschiefer" 
  

   series 
  ; 
  but 
  shortly 
  before 
  reaching 
  Mittersill 
  we 
  traverse 
  in 
  a 
  shallow 
  

   gorge 
  a 
  considerable 
  mass 
  of 
  chloritic 
  schist, 
  with 
  a 
  high 
  dip 
  towards 
  

   the 
  north 
  (Appendix, 
  p. 
  108). 
  It 
  is 
  somewhat 
  calcareous, 
  and 
  corre- 
  

   sponds 
  with 
  the 
  green 
  schists 
  in 
  the 
  glen 
  north 
  of 
  Windisch-Matrei. 
  

   According 
  to 
  Yon 
  Hauer's 
  map 
  the 
  associated 
  group 
  of 
  calcareous, 
  

   micaceous, 
  and 
  chloritic 
  schists 
  extends 
  continuously 
  round 
  the 
  

   eastern 
  edge 
  of 
  the 
  Central- 
  Gneiss 
  massif, 
  passing 
  from 
  Windisch- 
  

   Matrei, 
  by 
  the 
  head 
  of 
  the 
  Mollthal, 
  to 
  the 
  valley 
  of 
  the 
  Salza, 
  in 
  

   which, 
  among 
  level 
  water-meadows, 
  Mittersill 
  is 
  situated. 
  

  

  