﻿Geology 
  and 
  Mineralogy. 
  7'T 
  

  

  several 
  members 
  of 
  the 
  Survey. 
  The 
  aggregate 
  appropriation 
  

   for 
  the 
  Geological 
  Survey 
  for 
  this 
  year 
  Avas 
  a 
  little 
  over 
  one 
  million 
  

   dollars. 
  

  

  In 
  Mr. 
  Emmons's 
  report 
  on 
  work 
  in 
  the 
  Rocky 
  Mountain 
  Re- 
  

   gion, 
  the 
  following 
  results 
  regarding 
  the 
  Tintic 
  mining 
  region 
  of 
  

   IJtah 
  are 
  reported 
  : 
  

  

  " 
  Contrary 
  to 
  what 
  is 
  usually 
  the 
  case 
  in 
  Western 
  mining 
  dis- 
  

   tricts, 
  there 
  appears 
  to 
  have 
  been 
  no 
  genetic 
  connection 
  between 
  

   ore 
  deposition 
  and 
  eruptive 
  action, 
  for 
  it 
  has 
  been 
  proved 
  that 
  the 
  

   most 
  important 
  ore 
  bodies 
  — 
  viz., 
  those 
  entirely 
  inclosed 
  in 
  sedi- 
  

   mentary 
  rocks 
  — 
  were 
  formed 
  and 
  eroded 
  before 
  the 
  igneous 
  rocks 
  

   were 
  erupted." 
  

  

  " 
  The 
  complete 
  independence 
  of 
  the 
  ground-water 
  level 
  in 
  the 
  

   mine 
  in 
  sedimentary 
  and 
  those 
  in 
  igneous 
  rocks." 
  

  

  "As 
  a 
  consequence 
  of 
  the 
  depth 
  of 
  the 
  permanent 
  water 
  level 
  

   in 
  the 
  former 
  mines, 
  their 
  ores 
  have 
  been 
  very 
  largely 
  oxidized, 
  

   and 
  in 
  this 
  process 
  of 
  oxidation 
  there 
  has 
  been 
  a 
  remarkable 
  

   separation 
  of 
  the 
  minerals 
  according 
  to 
  their 
  metallic 
  bases, 
  lead 
  

   ores 
  predominating 
  at 
  one 
  point, 
  copper 
  ores 
  at 
  another, 
  and 
  silver 
  

   ores 
  at 
  a 
  third." 
  

  

  Mr. 
  Lindgren 
  reports, 
  regarding 
  Surveys 
  in 
  the 
  Snake 
  Valley, 
  

   the 
  following 
  : 
  

  

  " 
  This 
  reconnaissance 
  was 
  carried 
  on 
  near 
  the 
  line 
  where 
  the 
  

   great 
  Columbia 
  lava 
  flows 
  rest 
  against 
  the 
  older 
  ranges 
  of 
  granite 
  

   and 
  slate 
  in 
  the 
  Idaho 
  side, 
  and 
  showed 
  that 
  the 
  cause 
  of 
  the 
  great 
  

   fresh-water 
  lake 
  was 
  to 
  be 
  found 
  in 
  the 
  immense 
  lava 
  masses 
  

   barring 
  the 
  comparatively 
  narrow 
  outlet 
  of 
  a 
  wide 
  pre-Neocene 
  

   valley. 
  It 
  was 
  also 
  found 
  that 
  since 
  Neocene 
  times 
  the 
  Snake 
  and 
  

   Salmon 
  rivers 
  have 
  cut 
  gorges 
  from 
  4,000 
  to 
  6,000 
  feet 
  deep 
  

   through 
  these 
  lava 
  barriers, 
  equaled 
  in 
  grandeur 
  by 
  few 
  canyons 
  

   of 
  the 
  West." 
  In 
  the 
  Silver 
  City 
  mining 
  district 
  "transformation 
  

   or 
  pseudomorphism 
  of 
  a 
  primary 
  gangue 
  mineral, 
  probably 
  cal- 
  

   cite, 
  to 
  quartz 
  was 
  noted." 
  Also, 
  " 
  quartz 
  deposits 
  were 
  found 
  

   carrying 
  gold 
  and 
  silver 
  and 
  at 
  the 
  same 
  time 
  including 
  im- 
  

   prints 
  of 
  vegetable 
  organisms 
  — 
  a 
  proof 
  of 
  their 
  aqueous 
  origin." 
  

  

  Mr. 
  Turner 
  finds 
  in 
  the 
  Yosemite 
  region 
  evidence 
  of 
  " 
  two 
  

   periods 
  of 
  ice 
  expansion, 
  with 
  an 
  interglacial 
  period." 
  

  

  The 
  Director 
  having, 
  in 
  his 
  capacity 
  as 
  inspector 
  of 
  forest 
  

   reserves 
  in 
  the 
  northwest, 
  made 
  examination 
  of 
  the 
  Yellowstone, 
  

   recommends, 
  in 
  his 
  report 
  to 
  the 
  Secretary 
  of 
  the 
  Interior, 
  the 
  

   construction 
  of 
  new 
  roads 
  from 
  the 
  Grand 
  Canyon 
  Hotel, 
  down 
  

   the 
  river 
  to 
  Yancey's 
  and 
  thence 
  around 
  the 
  Cook 
  City 
  road 
  ; 
  

   and 
  also 
  several 
  horse 
  trails 
  for 
  the 
  convenience 
  of 
  those 
  who 
  

   would 
  go 
  on 
  horseback 
  off 
  from 
  the 
  traveled 
  road 
  to 
  points 
  of 
  

   interest. 
  Another 
  important 
  recommendation 
  is 
  that 
  a 
  hotel 
  be 
  

   built 
  at 
  the 
  Upper 
  Geyser 
  Basin 
  for 
  the 
  convenience 
  of 
  travelers; 
  

   and 
  another 
  important 
  suggestion 
  that 
  some 
  means 
  be 
  taken 
  to 
  

   allay 
  the 
  dust 
  nuisance 
  on 
  the 
  traveled 
  roads 
  in 
  the 
  park. 
  

  

  Mr. 
  Day's 
  report 
  on 
  the 
  Division 
  of 
  Mineral 
  Resources 
  shows 
  

   a 
  grand 
  total 
  of 
  mineral 
  products 
  of 
  the 
  United 
  States 
  for 
  1897 
  

  

  