﻿131 
  

  

  diffused 
  through 
  them, 
  like 
  the 
  masses 
  of 
  anthracite 
  found 
  in 
  those 
  from 
  

   Herkimer 
  county. 
  Occasionally 
  they 
  appear 
  almost 
  like 
  crystals 
  of 
  

   specular 
  iron 
  itself, 
  but 
  with 
  the 
  form 
  of 
  quartz. 
  It 
  is 
  probably 
  to 
  the 
  

   disintegration 
  of 
  this 
  ore 
  that 
  the 
  ochery 
  and 
  cavernous 
  appearance 
  of 
  

   these 
  crystals 
  is 
  to 
  be 
  ascribed. 
  

  

  The 
  Natural 
  bridge, 
  in 
  Lewis 
  county, 
  has 
  furnished 
  opaque 
  crystals 
  

   of 
  quartz 
  of 
  considerable 
  size, 
  and 
  presenting 
  some 
  interesting 
  modifi- 
  

   cations. 
  To 
  those 
  already 
  given, 
  I 
  can 
  now 
  add 
  that 
  whieh 
  is 
  here 
  

   figured, 
  and 
  which 
  is 
  remarkable, 
  as 
  exhibiting 
  only 
  three 
  terminal 
  

   faces. 
  

  

  According 
  to 
  Vanuxem, 
  hyalite 
  is 
  found 
  in 
  the 
  Potsdam 
  eandstone, 
  

   half 
  a 
  mile 
  below 
  Canajoharie, 
  in 
  Montgomery 
  count)^ 
  Report 
  on 
  the 
  

   Geol. 
  Uh 
  Dist., 
  p. 
  29. 
  

  

  TABULAR 
  SPAR. 
  

  

  (Mineralogy 
  of 
  New- 
  York, 
  page 
  270.) 
  

  

  Dr. 
  Emmons 
  states 
  that 
  fine 
  specimens 
  of 
  this 
  rather 
  rare 
  mineral 
  are 
  

   found 
  in 
  Keene, 
  Essex 
  county. 
  Geology 
  of 
  the 
  2d 
  Dist., 
  p. 
  286. 
  

  

  NEMALITE. 
  

  

  (Mineralogy 
  of 
  New- 
  York, 
  page 
  272.) 
  

   Prof. 
  Connell 
  has 
  recently 
  analyzed 
  this 
  mineral. 
  His 
  results 
  are 
  

   very 
  different 
  from 
  those 
  of 
  Dr. 
  Thomson, 
  but 
  he 
  operated 
  upon 
  a 
  very 
  

   small 
  portion. 
  They 
  are 
  as 
  follows, 
  viz 
  : 
  Magnesia, 
  57*86 
  ; 
  protoxide 
  of 
  

   iron, 
  2-84; 
  silica, 
  0*S0; 
  water, 
  27-96; 
  carbonic 
  acid, 
  10*00 
  ; 
  = 
  99*46. 
  

   He 
  supposes 
  the 
  formula 
  to 
  be, 
  5 
  Mg 
  0, 
  HO 
  •+■ 
  Mg 
  O, 
  C 
  2 
  H 
  O. 
  

  

  