﻿1864.] 
  BLAKE 
  NEVADA 
  TERRITORY. 
  319 
  

  

  in 
  Washoe 
  Valley, 
  beds 
  of 
  limestone 
  have 
  been 
  found. 
  Parallel 
  

   with 
  these 
  rocks 
  and 
  with 
  the 
  mountains, 
  thermal 
  springs 
  rise 
  in 
  a 
  

   line 
  through 
  the 
  drift 
  and 
  superficial 
  deposits, 
  sending 
  their 
  waters 
  

   into 
  the 
  marshes 
  of 
  the 
  low 
  ground, 
  in 
  the 
  middle 
  of 
  the 
  valley. 
  

  

  From 
  Genoa 
  to 
  Carson 
  City 
  the 
  road 
  follows 
  an 
  alluvial 
  and 
  

   sandy 
  plain. 
  Near 
  Carson 
  there 
  are 
  outcrops 
  of 
  horizontal 
  strata 
  of 
  

   coarse-grained 
  sandstone, 
  thickly 
  bedded, 
  showing 
  the 
  action 
  of 
  

   rapid 
  currents 
  during 
  its 
  formation, 
  and 
  probably 
  of 
  Tertiary 
  age. 
  

   These 
  strata 
  are 
  quarried 
  for 
  building-stone. 
  A 
  few 
  miles 
  beyond 
  

   there 
  is 
  an 
  outcrop 
  of 
  massive 
  porphyritic 
  conglomerate, 
  of 
  ancient 
  

   date 
  and 
  highly 
  inclined 
  stratification; 
  it 
  is 
  composed 
  of 
  boulders, 
  

   coarse 
  gravel, 
  and 
  angular 
  masses, 
  all 
  very 
  firmly 
  cemented 
  together 
  ; 
  

   it 
  is 
  evidently 
  much 
  metamorphosed, 
  and 
  may 
  be 
  a 
  portion 
  of 
  an 
  

   extended 
  formation. 
  Outcrojis 
  of 
  a 
  bluish-grey 
  rock, 
  like 
  a 
  meta- 
  

   morphic 
  sandstone, 
  were 
  seen 
  at 
  a 
  short 
  distance 
  beyond. 
  A 
  coarse 
  

   porphyritic 
  conglomerate, 
  similar 
  to 
  that 
  described, 
  is 
  extensively 
  de- 
  

   veloped 
  in 
  the 
  silver 
  region 
  of 
  Arizona. 
  

  

  Leaving 
  these 
  ridges, 
  and 
  traversing 
  a 
  dusty 
  plain, 
  horizontal 
  

   strata 
  make 
  their 
  appearance 
  on 
  the 
  sides 
  of 
  a 
  slight 
  declivity, 
  

   called 
  Chalk 
  Mountains, 
  by 
  which 
  the 
  road 
  descends 
  to 
  a 
  lower 
  

   plain. 
  These 
  strata 
  are 
  white 
  and 
  very 
  soft. 
  Similar 
  rocks 
  occur 
  

   in 
  other 
  parts 
  of 
  the 
  Territory, 
  and 
  are 
  compact, 
  smooth, 
  and 
  soft, 
  

   so 
  that 
  they 
  may 
  be 
  cut 
  and 
  carved 
  like 
  meerschaum. 
  Some 
  frag- 
  

   ments 
  of 
  this 
  rock 
  placed 
  under 
  a 
  microscope 
  did 
  not, 
  however, 
  

   show 
  any 
  traces 
  of 
  organized 
  structures. 
  This 
  white 
  formation 
  is 
  

   probably 
  conformable 
  with, 
  and 
  lies 
  above, 
  the 
  horizontal 
  sandstones 
  

   at 
  the 
  springs 
  near 
  Carson. 
  

  

  Near 
  the 
  lower 
  part 
  of 
  Gold 
  Canon, 
  below 
  Silver 
  City, 
  the 
  road 
  

   deflects 
  from 
  the 
  Overland 
  Mail 
  Route, 
  or 
  Old 
  Emigrant 
  Road, 
  and 
  

   ascends 
  the 
  lower 
  slopes 
  of 
  the 
  south 
  end 
  of 
  the 
  Washoe 
  or 
  Silver 
  

   .Range. 
  Here 
  rugged 
  outcrops 
  of 
  a 
  compact, 
  light- 
  coloured, 
  fel- 
  

   spathic 
  porphyry 
  are 
  numerous, 
  and 
  their 
  debris 
  covers 
  the 
  ground. 
  

   These 
  porphyries 
  are 
  traversed 
  by 
  many 
  veins 
  of 
  quartz 
  with 
  their 
  

   crystals 
  pointing 
  inwards, 
  as 
  in 
  true 
  fissure-veins 
  ; 
  they 
  are 
  very 
  

   numerous, 
  and 
  from 
  a 
  few 
  inches 
  to 
  many 
  feet 
  in 
  width. 
  The 
  

   ground 
  is 
  in 
  every 
  direction 
  covered 
  with 
  their 
  fragments, 
  which 
  

   have 
  been 
  broken 
  out 
  by 
  weathering, 
  or 
  by 
  the 
  gradual 
  decay 
  of 
  the 
  

   enveloping 
  porphyry. 
  The 
  size 
  and 
  number 
  of 
  these 
  loose 
  vein- 
  

   stones 
  increase 
  as 
  Gold 
  Canon 
  is 
  ascended, 
  up 
  to 
  its 
  head 
  on 
  the 
  

   side 
  of 
  Mount 
  Davidson. 
  

  

  Mount 
  Davidson 
  is 
  the 
  principal 
  peak 
  of 
  the 
  Washoe 
  Range, 
  and 
  

   a 
  central 
  point 
  and 
  landmark 
  of 
  the 
  Washoe 
  Region. 
  The 
  Corn- 
  

   stock 
  Lode, 
  Goldhill 
  Lode, 
  and 
  others 
  cut 
  its 
  eastern 
  flank 
  towards 
  

   the 
  base, 
  the 
  latter 
  at 
  the 
  head 
  of 
  Gold 
  Canon, 
  and 
  the 
  former 
  a 
  

   mile 
  or 
  two 
  beyond, 
  at 
  the 
  head 
  of 
  Six-mile 
  Canon, 
  extending 
  east- 
  

   wardly 
  to 
  the 
  plains 
  of 
  the 
  Carson. 
  The 
  whole 
  of 
  this 
  mountain, 
  

   and, 
  indeed, 
  the 
  greater 
  part 
  of 
  the 
  Washoe 
  Range, 
  between 
  Vir- 
  

   ginia 
  City 
  and 
  Washoe 
  Lake, 
  are 
  composed 
  of 
  fine-grained, 
  light- 
  

   coloured 
  felspar-porphyry, 
  quartz-porphyry, 
  and 
  porphyritic 
  green- 
  

   stones, 
  with 
  some 
  basalts 
  and 
  overlying 
  volcanic 
  rocks. 
  So 
  also, 
  

  

  2 
  a2 
  

  

  