﻿26 
  REPORT 
  UNITED 
  gTATES 
  GEOLOGICAL 
  SURVEY. 
  • 
  

  

  the 
  labors 
  of 
  such 
  preeminent 
  palseontologists 
  as 
  Joseph 
  Leidy, 
  E. 
  D. 
  

   Cope, 
  F. 
  B. 
  Meek, 
  Leo 
  Lesquereux, 
  and 
  others, 
  whose 
  results 
  are 
  boyond 
  

   praise. 
  

  

  During 
  the 
  progress 
  of 
  the 
  survey 
  of 
  Colorado, 
  several 
  preliminary 
  

   maps, 
  on 
  small 
  scales, 
  have 
  been 
  published 
  in 
  the 
  Reports. 
  Of 
  these 
  it 
  

   is 
  necessary 
  to 
  specify 
  but 
  a 
  few. 
  

  

  In 
  the 
  report 
  of 
  the 
  field-work 
  of 
  1873, 
  there 
  is 
  a 
  drainage-map 
  of 
  the 
  

   area 
  surveyed 
  — 
  18,000 
  square 
  miles 
  — 
  on 
  a 
  scale 
  of 
  eight 
  miles 
  to 
  one 
  

   inch. 
  

  

  The 
  Eeport 
  for 
  1874 
  contains 
  a 
  preliminary 
  map 
  in 
  hachui-es, 
  on 
  a 
  scale 
  

   of 
  ten 
  miles 
  to 
  one 
  inch, 
  of 
  all 
  the 
  work 
  done 
  in 
  the 
  State 
  up 
  to 
  that 
  

   time; 
  a 
  map 
  of 
  the 
  Elk 
  Mountains, 
  topographical 
  and 
  geological, 
  on 
  a 
  

   scale 
  of 
  two 
  miles 
  to 
  one 
  inch 
  ; 
  and 
  a 
  preliminary 
  map 
  of 
  the 
  eastern 
  

   front 
  of 
  the 
  Eocky 
  Mountains, 
  on 
  a 
  scale 
  of 
  four 
  miles 
  to 
  one 
  inch. 
  

  

  Owing 
  to 
  the 
  need 
  of 
  the 
  settlers, 
  a 
  drainage-map 
  of 
  the 
  San 
  Juan 
  

   country, 
  on 
  a 
  scale 
  of 
  four 
  miles 
  to 
  the 
  inch, 
  was 
  also 
  issued, 
  and 
  after- 
  

   ward 
  incorporated 
  in 
  the 
  Eeport. 
  Besides 
  these, 
  there 
  are 
  many 
  small 
  

   geological 
  maps 
  of 
  special 
  areas. 
  

  

  The 
  atlas 
  of 
  Colorado, 
  now 
  nearly 
  ready, 
  will 
  contain 
  : 
  — 
  

  

  First. 
  Title-page, 
  legend-sheet, 
  and 
  map 
  of 
  the 
  primary 
  triangulation. 
  

  

  Second. 
  A 
  general 
  drainage-map 
  of 
  the 
  State, 
  on 
  a 
  scale 
  of 
  twelve 
  

   miles 
  to 
  one 
  inch. 
  

  

  Third. 
  An 
  economic 
  map, 
  colored 
  to 
  represent 
  areas 
  of 
  arable, 
  pasture, 
  

   timber 
  land, 
  etc. 
  

  

  Fourth. 
  The 
  final 
  map 
  of 
  the 
  State 
  (including 
  small 
  parts 
  of 
  New 
  

   Mexico, 
  Arizona, 
  and 
  Utah), 
  in 
  six 
  sheets, 
  on 
  a 
  scale 
  of 
  four 
  miles 
  to 
  

   one 
  inch, 
  in 
  contours 
  200 
  feet 
  apart 
  in 
  vertical 
  distance. 
  The 
  area 
  em- 
  

   braced 
  in 
  these 
  maps 
  is 
  about 
  70,000 
  square 
  miles. 
  

  

  Fifth. 
  The 
  final 
  geological 
  map 
  of 
  Colorado, 
  in 
  six 
  sheets. 
  

  

  Sixth. 
  A 
  general 
  geological 
  map 
  of 
  the 
  State 
  on 
  a 
  scale 
  of 
  twelve 
  

   miles 
  to 
  an 
  inch. 
  

  

  Seventh. 
  Two 
  sheets 
  containing 
  the 
  general 
  sections 
  across 
  the 
  State, 
  

   illustrating 
  the 
  geological 
  map. 
  

  

  Eighth. 
  Two 
  sheets 
  of 
  panoramic 
  views. 
  

  

  When 
  finished, 
  Colorado 
  will 
  have 
  a 
  better 
  map 
  than 
  any 
  other 
  State 
  

   in 
  the 
  Union, 
  and 
  the 
  work 
  will 
  be 
  of 
  such 
  a 
  character 
  that 
  it 
  will 
  never 
  

   need 
  to 
  be 
  done 
  again. 
  Colorado 
  will 
  never 
  support 
  so 
  dense 
  a 
  popula- 
  

   tion 
  that 
  a 
  more 
  detailed 
  survey 
  will 
  be 
  required. 
  Accurately 
  located 
  

   points 
  on 
  which 
  the 
  local 
  surveyors 
  can 
  base 
  their 
  work 
  are 
  abundant 
  

   in 
  all 
  parts 
  of 
  the 
  St-ate. 
  The 
  work 
  of 
  the 
  geological 
  survey 
  should 
  

   always 
  precede 
  that 
  of 
  the 
  laud 
  survey, 
  as 
  the 
  former 
  indicates 
  what 
  por- 
  

   tions 
  of 
  the 
  country 
  are 
  suited 
  for 
  settlement 
  and 
  should 
  be 
  sectionized. 
  

  

  It 
  is 
  the 
  intention 
  of 
  the 
  Survey 
  to 
  continue 
  the 
  collection 
  of 
  all 
  geo- 
  

   graphical 
  data 
  concerning 
  the 
  relief 
  of 
  the 
  country 
  west 
  of 
  the 
  Missis- 
  

   sippi 
  Eiver. 
  These 
  collections 
  of 
  heights 
  have 
  been 
  published 
  from 
  

   time 
  to 
  time, 
  in 
  a 
  succession 
  of 
  editions, 
  under 
  the 
  title 
  of 
  " 
  Lists 
  of 
  

  

  