﻿152 
  G. 
  II. 
  Stone 
  — 
  Asphaltum 
  of 
  Utah 
  and 
  Colorado. 
  

  

  has 
  invaded 
  it 
  or 
  its 
  under-clay 
  from 
  the 
  asphalt 
  layer. 
  The 
  

   coal 
  abounds 
  in 
  lumps 
  of 
  yellow, 
  partially 
  mineralized 
  rosin, 
  

   just 
  like 
  most 
  of 
  the 
  softer 
  coals 
  of 
  the 
  mountain 
  region. 
  

  

  In 
  the 
  Wasatch 
  and 
  Roan 
  Mountains 
  I 
  have 
  in 
  several 
  places 
  

   found 
  coal 
  seams 
  up 
  to 
  eighteen 
  inches 
  in 
  thickness 
  with 
  the 
  

   bituminous 
  Green 
  River 
  shales 
  and 
  limestones 
  both 
  above 
  and 
  

   below 
  them. 
  Here 
  the 
  conditions 
  for 
  the 
  formation 
  of 
  coal 
  

   and 
  asphalt 
  rocks 
  alternated. 
  

  

  Both 
  the 
  bituminous 
  rocks 
  and 
  the 
  coal 
  beds 
  are 
  substantially 
  

   conformable 
  to 
  the 
  bedding, 
  and 
  both 
  are 
  somewhat 
  lenticular. 
  

  

  A 
  few 
  years 
  ago, 
  Mr. 
  C. 
  A. 
  Ashburner 
  proposed 
  as 
  a 
  basis 
  

   of 
  classification 
  of 
  coals 
  the 
  ratio 
  of 
  fixed 
  carbon 
  to 
  volatile 
  

   carbonaceous 
  matter. 
  As 
  I 
  understand 
  it 
  the 
  term 
  "fixed 
  

   carbon 
  " 
  does 
  not 
  assume 
  that 
  all 
  the 
  carbon 
  thus 
  designated 
  

   exists 
  in 
  the 
  coal 
  as 
  carbon 
  uncombined 
  with 
  hydrogen, 
  etc., 
  

   but 
  refers 
  to 
  the 
  residue 
  after 
  destructive 
  distillation. 
  It 
  

   remains 
  to 
  be 
  determined 
  how 
  far 
  this 
  test 
  will 
  apply 
  to 
  the 
  

   asphalt. 
  In 
  western 
  Colorado 
  and 
  Utah 
  we 
  find 
  in 
  the 
  car- 
  

   bonaceous 
  minerals 
  all 
  proportions 
  of 
  fixed 
  carbon 
  from 
  one 
  or 
  

   two 
  per 
  cent 
  in 
  the 
  maltha 
  up 
  to 
  eighty-seven 
  or 
  more 
  in 
  the 
  

   anthracite. 
  The 
  soft 
  asphalts 
  grade 
  by 
  insensible 
  degrees 
  into 
  

   the 
  hard 
  asphalts 
  (at 
  least 
  in 
  their 
  physical 
  characteristics) 
  and 
  

   these 
  in 
  turn 
  into 
  jet, 
  the 
  cannel 
  coals 
  and 
  bituminous 
  shales, 
  

   and 
  these 
  again 
  into 
  the 
  caking 
  coals, 
  etc. 
  Dana's 
  Text-book 
  of 
  

   Mineralogy 
  approves 
  the 
  theory 
  that 
  coals 
  are 
  chiefly 
  composed 
  

   of 
  oxygenated 
  hydro-carbons. 
  In 
  the 
  Rocky 
  Mountain 
  region 
  

   not 
  only 
  must 
  a 
  scientific 
  classification 
  of 
  the 
  coals 
  take 
  account 
  

   of 
  the 
  oxygen 
  contained 
  in 
  the 
  different 
  coals, 
  but 
  the 
  indus- 
  

   trial 
  classification 
  must 
  do 
  the 
  same 
  also. 
  Many 
  coals 
  of 
  this 
  

   region 
  when 
  once 
  inflamed 
  will 
  continue 
  to 
  burn 
  for 
  a 
  long 
  

   time 
  even 
  when 
  protected 
  from 
  the 
  air. 
  This 
  accounts 
  for 
  the 
  

   long 
  distances 
  the 
  lignites 
  often 
  burn 
  under 
  ground. 
  On 
  East 
  

   Salt 
  Creek, 
  Col., 
  the 
  burning 
  coal 
  produced 
  a 
  layer 
  of 
  slag 
  of 
  

   unequal 
  thickness 
  up 
  to 
  twelve 
  feet 
  and 
  the 
  country 
  shows 
  the 
  

   action 
  of 
  hot 
  waters 
  much 
  like 
  a 
  volcanic 
  region. 
  Several 
  

   places 
  are 
  known 
  where 
  the 
  coal 
  adjacent 
  to 
  the 
  once 
  burning 
  

   coal 
  has 
  been 
  changed 
  to 
  a 
  natural 
  coke, 
  and 
  as 
  we 
  go 
  back- 
  

   ward 
  from 
  the 
  former 
  fire 
  the 
  coke 
  passes 
  by 
  degrees 
  into 
  the 
  

   unaltered 
  caking 
  coal. 
  

  

  Origin 
  of 
  the 
  Asphalt. 
  — 
  When 
  the 
  facts 
  as 
  to 
  the 
  Utah 
  and 
  

   Colorado 
  bitumens 
  are 
  thoroughly 
  collated 
  and 
  discussed, 
  they 
  

   will 
  throw 
  considerable 
  light 
  on 
  the 
  mooted 
  questions 
  as 
  to 
  the 
  

   origin 
  of 
  petroleum, 
  asphalt, 
  gas, 
  and 
  other 
  subterranean 
  hydro- 
  

   carbons. 
  Most 
  other 
  areas 
  were 
  marine, 
  while 
  these 
  deposits 
  

   were 
  made 
  in 
  the 
  sediments 
  of 
  the 
  extensive 
  lakes 
  which 
  in 
  

   Tertiary 
  times 
  extended 
  from 
  the 
  Rocky 
  Mountains 
  several 
  

   hundred 
  miles 
  westward. 
  These 
  rocks 
  will 
  therefore 
  present 
  

   conditions 
  somewhat 
  different 
  from 
  those 
  of 
  marine 
  beds. 
  

  

  