﻿ADIRONDACK 
  MAGNETIC 
  IRON 
  ORES 
  6l 
  

  

  of 
  Swedish 
  type. 
  Explorations 
  with 
  the 
  diamond 
  drill 
  then 
  

   follow. 
  

  

  From 
  Mineville 
  southward 
  through 
  Moriah 
  Center, 
  Moriah 
  

   (locally 
  called 
  " 
  The 
  Corners 
  ") 
  and 
  still 
  farther, 
  the 
  mantle 
  of 
  drift 
  

   extends 
  with 
  comparatively 
  few 
  exposures 
  of 
  the 
  bed 
  rock. 
  Just 
  

   east 
  of 
  Moriah 
  Center, 
  Mill 
  brook 
  has 
  cut 
  into 
  it 
  fully 
  ioo 
  feet 
  

   without 
  reaching 
  the 
  rock 
  bottom. 
  Presumably 
  the 
  expiring 
  

   glacial 
  activity 
  filled 
  the 
  valley 
  and 
  the 
  movement 
  was 
  probably 
  

   from 
  the 
  northeast 
  since 
  such 
  scratches 
  as 
  remain 
  in 
  the 
  general 
  

   region 
  run 
  n. 
  5o°-6o° 
  e. 
  The 
  boulders 
  seldom 
  attain 
  the 
  gigantic 
  

   size 
  sometimes 
  shown 
  farther 
  within 
  the 
  mountains 
  but 
  individ- 
  

   uals 
  up 
  to 
  6 
  or 
  8 
  feet 
  are 
  not 
  uncommon. 
  

  

  Paleozoic 
  sediments. 
  These 
  strata 
  are 
  practically 
  limited 
  to 
  the 
  

   lake 
  shore 
  in 
  the 
  region 
  under 
  consideration. 
  The 
  Potsdam 
  pro- 
  

   jects 
  up 
  the 
  valley 
  of 
  McKenzie 
  brook 
  for 
  perhaps 
  half 
  a 
  mile 
  from 
  

   the 
  water, 
  but 
  ceases 
  long 
  before 
  it 
  is 
  concerned 
  with 
  any 
  mines. 
  

   No 
  further 
  mention 
  is 
  therefore 
  made 
  of 
  any 
  of 
  them. 
  

  

  Diabase 
  dikes. 
  These 
  interesting 
  narrow 
  bodies 
  of 
  dark 
  basaltic 
  

   rock 
  are 
  widespread 
  and 
  of 
  no 
  small 
  scientific 
  interest. 
  Through- 
  

   out 
  the 
  Adirondacks 
  they 
  appear 
  not 
  uncommonly 
  in 
  the 
  mines, 
  

   and 
  usually 
  occupy 
  a 
  fault 
  line 
  by 
  which 
  the 
  ore 
  is 
  thrown 
  varying 
  

   distances 
  up 
  to 
  30 
  or 
  40 
  feet. 
  They 
  strike 
  in 
  two 
  principal 
  direc- 
  

   tions, 
  a 
  northeast 
  set, 
  embracing 
  about 
  three 
  quarters 
  of 
  the 
  known 
  

   instances 
  and 
  an 
  east 
  and 
  west 
  set, 
  including 
  almost 
  all 
  the 
  rest. 
  

   In 
  only 
  one 
  or 
  two 
  instances 
  have 
  they 
  been 
  observed 
  with 
  a 
  north- 
  

   west 
  strike. 
  These 
  directions 
  correspond 
  with 
  the 
  chief 
  structural 
  

   breaks, 
  and 
  undoubtedly 
  in 
  seeking 
  a 
  path 
  to 
  the 
  upper 
  world 
  the 
  

   dikes 
  have 
  merely 
  followed 
  the 
  lines 
  of 
  least 
  resistance. 
  

  

  At 
  Mineville, 
  one, 
  with 
  an 
  east 
  and 
  west 
  strike 
  is 
  known 
  in 
  the 
  

   Joker 
  working; 
  two 
  or 
  three, 
  with 
  a 
  northeast 
  strike 
  cut 
  the 
  Har- 
  

   mony 
  bed; 
  one 
  appears 
  in 
  the 
  Miller 
  pit, 
  which 
  is 
  probably 
  con- 
  

   tinuous 
  with 
  one 
  of 
  those 
  in 
  the 
  Harmony 
  bed, 
  and 
  another 
  was 
  

   reported 
  from 
  the 
  Old 
  Bed 
  workings 
  in 
  former 
  years. 
  The 
  rocks 
  

   are 
  all 
  badly 
  decomposed 
  and 
  not 
  in 
  good 
  condition 
  for 
  careful 
  

   determination. 
  It 
  is 
  necessary 
  to 
  exercise 
  care 
  lest 
  the 
  darkened 
  

   and 
  chloritized 
  breccias 
  along 
  faults 
  be 
  mistaken 
  for 
  them. 
  

  

  In 
  the 
  Cheever 
  mine 
  a 
  number 
  of 
  dikes 
  were 
  met 
  in 
  former 
  years 
  

   and 
  have 
  been 
  figured 
  by 
  B. 
  T. 
  Putnam. 
  1 
  The 
  strike 
  is 
  not 
  

   recorded 
  and 
  may 
  be 
  judged 
  only 
  from 
  the 
  fact 
  that 
  the 
  dikes 
  

  

  1 
  Report 
  on 
  the 
  Mining 
  Industries 
  of 
  the 
  United 
  States, 
  Tenth 
  Census, 
  

   v. 
  XV. 
  

  

  