﻿No. 
  30.] 
  85 
  

  

  prism 
  witli 
  low, 
  three-sided 
  pyramids 
  as 
  terminations. 
  Great 
  

   similarity 
  exists 
  among 
  the 
  crystals 
  of 
  this 
  locality, 
  and 
  the 
  ac- 
  

   companying 
  sketch, 
  fig. 
  10, 
  represents 
  a 
  very 
  prevalent 
  compound 
  

   form. 
  

  

  30. 
  Potsdam 
  sandstone, 
  with 
  lines 
  apparently 
  of 
  stratification, 
  

  

  crossing 
  it 
  in 
  two 
  directions, 
  

  

  31. 
  Spinelle. 
  This 
  mineral 
  occurs 
  in 
  Rossie, 
  near 
  Somerville, 
  

  

  associated 
  with 
  chondrodite, 
  graphite, 
  &c., 
  in 
  white 
  

   limestone, 
  

   32,33,34,35, 
  Chondrodite. 
  Locality 
  of 
  preceding. 
  

  

  This 
  mineral, 
  hitherto 
  rare 
  in 
  northern 
  New- 
  York, 
  was 
  found 
  

   in 
  great 
  quantity 
  in 
  the 
  spring 
  of 
  1850, 
  in 
  white 
  limestone, 
  with 
  

   its 
  usual 
  associates 
  of 
  spinelle 
  and 
  small 
  quantities 
  of 
  graphite. 
  

  

  It 
  is 
  disseminated 
  throughout 
  a 
  ledge 
  of 
  white 
  limestone, 
  and 
  

   •exists 
  in 
  great 
  abundance. 
  The 
  locality 
  is 
  three-fourths 
  of 
  a 
  mile 
  

   W. 
  N. 
  W. 
  of 
  Somerville 
  villag-e, 
  on 
  the 
  land 
  of 
  Mr. 
  Alfred 
  Day. 
  

   The 
  mineral 
  occurs 
  of 
  various 
  shades 
  of 
  yellow 
  and 
  orange, 
  some- 
  

   times 
  inclining 
  to 
  red. 
  The 
  spinelle 
  is 
  of 
  a 
  dull 
  reddish 
  tinge, 
  and 
  

   in 
  small 
  crystals 
  translucent. 
  The 
  largest 
  crystals 
  observed 
  

   (I 
  of 
  an 
  inch 
  on 
  a 
  side) 
  were 
  opake, 
  but 
  the 
  faces 
  of 
  the 
  crystals 
  

   -are 
  usually 
  smooth 
  and 
  bright. 
  

  

  The 
  singular 
  association 
  of 
  these 
  minerals 
  has 
  been 
  observed 
  in 
  

   Orange 
  county, 
  and 
  other 
  sections 
  of 
  the 
  Union. 
  This 
  is 
  the 
  first 
  

   abundant 
  locality 
  observed 
  in 
  St. 
  Lawrence 
  county. 
  See 
  State 
  

   Mineralogy, 
  page 
  282. 
  

  

  36 
  to 
  39. 
  Pearl 
  star. 
  Associated 
  with 
  calcareous 
  spar, 
  (No. 
  

   1-20.) 
  Rossie. 
  

  

  40,41. 
  Sphene. 
  Found 
  in 
  a 
  hornblende 
  boulder, 
  associated 
  

   with 
  crystals 
  of 
  the 
  latter 
  minerals. 
  Rossie, 
  St. 
  Law- 
  

   rence 
  county. 
  

  

  42. 
  Crystalized 
  cast 
  iron. 
  From 
  the 
  furnace 
  of 
  Messrs. 
  Skin- 
  

   ner 
  and 
  Blish, 
  Church's 
  Mills. 
  Rossie. 
  

  

  This 
  most 
  interesting 
  specimen, 
  with 
  three 
  or 
  four 
  others, 
  was 
  

   produced 
  in 
  the 
  fall 
  of 
  1849, 
  by 
  the 
  concurrence 
  of 
  numerous 
  cir- 
  

   cumstances 
  which 
  seldom 
  coincide. 
  Having 
  shown 
  this 
  forma- 
  

   tion 
  to 
  numerous 
  practical 
  founders 
  and 
  iron 
  manufacturers, 
  and 
  

  

  