﻿1864.] 
  BLAKE 
  NEVADA 
  TERRITORY. 
  323 
  

  

  sounded 
  to 
  any 
  great 
  depth. 
  A 
  constant 
  gurgling 
  sound 
  is 
  heard, 
  

   like 
  water 
  boiling, 
  and 
  the 
  ebullition 
  may 
  be 
  seen 
  in 
  some 
  places 
  

   about 
  ten 
  feet 
  below 
  the 
  surface 
  of 
  the 
  crest. 
  The 
  steam 
  does 
  not 
  rise 
  

   equally 
  along 
  the 
  whole 
  length 
  of 
  the 
  fissure, 
  but 
  escapes 
  at 
  intervals, 
  

   as 
  if 
  it 
  were 
  confined 
  in 
  tube-like 
  channels 
  or 
  pipes 
  below, 
  and 
  with 
  

   a 
  puffing 
  noise 
  like 
  that 
  of 
  a 
  steam-engine 
  — 
  whence 
  their 
  name. 
  

  

  The 
  water 
  appears 
  to 
  stand 
  and 
  cool 
  in 
  the 
  fissures, 
  while 
  the 
  

   steam 
  bubbles 
  through 
  it 
  at 
  different 
  points. 
  At 
  the 
  extreme 
  ends 
  

   of 
  the 
  mound, 
  and 
  on 
  its 
  flank, 
  there 
  are 
  several 
  basin-shaped 
  

   springs 
  or 
  caldrons, 
  from 
  which 
  hot 
  water 
  and 
  steam 
  rise 
  together, 
  

   some 
  of 
  them 
  spouting 
  upwards 
  and 
  overflowing 
  at 
  intervals. 
  In 
  

   one 
  of 
  the 
  largest 
  of 
  these 
  intermittent 
  springs 
  the 
  water 
  stands 
  

   quietly 
  about 
  two 
  feet 
  below 
  the 
  top 
  of 
  the 
  basin, 
  and, 
  at 
  regular 
  

   intervals 
  of 
  about 
  four 
  minutes, 
  suddenly 
  rises 
  in 
  violent 
  ebullition 
  

   and 
  flows 
  out. 
  

  

  This 
  mound, 
  some 
  two 
  or 
  three 
  acres 
  in 
  extent, 
  and 
  as 
  white 
  as 
  

   chalk, 
  consists 
  chiefly 
  of 
  silica 
  (siliceous 
  sinter), 
  deposited 
  by 
  the 
  

   water 
  in 
  an 
  amorphous 
  granular 
  state. 
  The 
  deposition 
  in 
  the 
  basin- 
  

   shaped 
  springs 
  is 
  very 
  rapid, 
  and 
  forms 
  elevated 
  annular 
  mounds. 
  

   Where 
  the 
  water 
  stands 
  in 
  pools, 
  the 
  silex 
  forms 
  crusts 
  like 
  ice 
  

   around 
  the 
  edges. 
  In 
  trickling 
  down 
  it 
  forms 
  stalactites, 
  or 
  partly 
  

   covers 
  the 
  currents 
  running 
  over 
  slopes. 
  Layer 
  after 
  layer 
  is 
  depo- 
  

   sited 
  on 
  inclined 
  surfaces, 
  and 
  some 
  very 
  good 
  examples 
  of 
  the 
  

   formation 
  of 
  banded 
  agate 
  and 
  chalcedony 
  were 
  seen, 
  the 
  colour 
  

   being 
  given 
  by 
  oxide 
  of 
  iron 
  and 
  by 
  organic 
  matters, 
  though 
  in 
  

   general 
  the 
  deposit 
  was 
  white. 
  At 
  some 
  of 
  the 
  springs 
  a 
  thin 
  black 
  

   film 
  -like 
  oxide 
  of 
  manganese 
  is 
  deposited 
  in 
  the 
  basin, 
  where 
  the 
  

   heat 
  is 
  greatest, 
  while 
  the 
  water 
  that 
  flows 
  away 
  deposits 
  sesqui- 
  

   oxide 
  of 
  iron 
  beyond. 
  Neither 
  the 
  specimens 
  of 
  the 
  deposits 
  nor 
  of 
  

   the 
  water 
  have 
  yet 
  been 
  analysed. 
  

  

  Sulphur 
  is 
  abundantly 
  produced 
  and 
  deposited 
  among 
  the 
  cavities 
  

   and 
  fissures 
  of 
  the 
  siliceous 
  crust, 
  especially 
  around 
  some 
  of 
  the 
  

   steam-jets 
  when 
  the 
  escape 
  is 
  through 
  the 
  fragments 
  or 
  loose 
  debris 
  

   of 
  the 
  fissure. 
  It 
  occurs 
  largely 
  in 
  crusts, 
  and 
  in 
  small 
  crystals 
  coat- 
  

   ing 
  the 
  fragments. 
  

  

  There 
  are 
  several 
  remains 
  of 
  old 
  basins 
  upon 
  the 
  upper 
  level 
  of 
  

   the 
  mound, 
  where 
  the 
  former 
  overflowing 
  of 
  the 
  springs 
  is 
  evident. 
  

   These 
  are 
  now 
  cut 
  through 
  by 
  the 
  fissures, 
  so 
  that 
  the 
  water 
  falls 
  

   to 
  the 
  level 
  of 
  the 
  lower 
  springs, 
  and 
  overflows 
  at 
  these 
  only. 
  The 
  

   new 
  fissure 
  appears 
  to 
  have 
  followed 
  the 
  line 
  of 
  the 
  principal 
  jets 
  ; 
  

   and 
  this 
  change 
  must 
  have 
  taken 
  place 
  within 
  a 
  few 
  years, 
  for 
  the 
  

   old 
  basins 
  are 
  yet 
  very 
  perfect 
  in 
  form, 
  half 
  being 
  on 
  one 
  side 
  of 
  

   the 
  fissure 
  and 
  half 
  on 
  the 
  other. 
  This 
  cracking 
  of 
  the 
  superficial 
  

   deposits 
  is 
  evidently 
  the 
  result 
  of 
  the 
  widening 
  of 
  the 
  ancient 
  fissure 
  

   in 
  the 
  rock 
  below. 
  

  

  We 
  may 
  regard 
  the 
  whole 
  as 
  a 
  fine 
  example 
  of 
  the 
  formation 
  of 
  

   a 
  quartz 
  vein 
  along 
  a 
  fissure; 
  for 
  there 
  is] 
  little 
  doubt 
  that, 
  if 
  the 
  

   superficial 
  deposits 
  were 
  swept 
  away 
  down 
  to 
  the 
  granite 
  or 
  por- 
  

   phyry, 
  we 
  should 
  find 
  a 
  fissure 
  lined 
  with 
  quartz, 
  and 
  perhaps 
  with 
  

   sulphurets 
  of 
  the 
  metals. 
  

  

  