﻿Compositio7i 
  of 
  the 
  Trap 
  of 
  Rocky 
  Hill^ 
  N. 
  J. 
  285 
  

  

  3d. 
  The 
  slow 
  cooling 
  to 
  which 
  it 
  has 
  been 
  subjected 
  

   coupled 
  with 
  tendency 
  of 
  the 
  anorthite 
  molecule 
  to 
  separate 
  at 
  

   a 
  higher 
  temperature, 
  has 
  concentrated 
  the 
  more 
  acid 
  feldspars 
  

   in 
  the 
  portion 
  last 
  to 
  consolidate, 
  to 
  such 
  an 
  extent 
  that 
  its 
  

   mineralogical 
  composition 
  is 
  almost 
  that 
  of 
  a 
  diorite. 
  

  

  4th. 
  From 
  the 
  character 
  of 
  the 
  decomposition 
  of 
  the 
  olivine, 
  

   and 
  the 
  solution 
  cavities 
  in 
  the 
  diallage 
  crystals, 
  the 
  intrusive 
  

   nature 
  of 
  this 
  dike 
  is 
  without 
  doubt, 
  as 
  this 
  must 
  have 
  taken 
  

   place 
  at 
  considerable 
  depths 
  from 
  the 
  surface, 
  and 
  under 
  very 
  

   heavy 
  pressure. 
  

  

  John 
  0. 
  Green 
  School 
  of 
  Science. 
  Princeton 
  University, 
  

   New 
  Jersey, 
  June, 
  '99. 
  

  

  Literature 
  Cited. 
  

  

  ^ 
  For 
  analyses 
  see 
  : 
  G. 
  H. 
  Cook, 
  Geology 
  of 
  New 
  .Jersey, 
  

   1868; 
  G» 
  W. 
  Hawes, 
  Tra]> 
  Rocks 
  of 
  the 
  Conn. 
  Valley, 
  this 
  

   Journal, 
  3d 
  series, 
  vol. 
  ix 
  ; 
  H. 
  D. 
  Cam|)bell 
  and 
  W. 
  G. 
  Brown, 
  

   Geol. 
  Soc. 
  of 
  Am., 
  Bull. 
  2, 
  1891, 
  p. 
  346; 
  Dr. 
  F. 
  A. 
  Genth, 
  2nd, 
  

   Geo]. 
  Survey 
  ol 
  Pa., 
  Report 
  on 
  progress 
  in 
  York 
  and 
  Adams 
  Co., 
  

   p. 
  120. 
  

  

  ^ 
  J. 
  D. 
  Dana, 
  this 
  Journal, 
  3d 
  series, 
  vol. 
  ix, 
  p. 
  191. 
  

   * 
  G. 
  W. 
  Hawes, 
  Proc. 
  U. 
  S. 
  National 
  Museum, 
  vol. 
  iv, 
  1881, 
  

   p. 
  132. 
  

  

  " 
  H. 
  D. 
  Campbell 
  and 
  W. 
  G. 
  Brown, 
  1. 
  c, 
  p. 
  341. 
  

   ' 
  See 
  New 
  Jersey 
  Geol. 
  Report 
  for 
  1896, 
  p. 
  34. 
  

   ' 
  N. 
  H. 
  Darton, 
  Bull. 
  U. 
  S. 
  Geol. 
  Sur., 
  No. 
  67. 
  

   ^ 
  E. 
  C. 
  E. 
  Lord, 
  Am. 
  Geologist, 
  vol. 
  xxii. 
  No. 
  6. 
  

   ^ 
  J. 
  P. 
  Iddings, 
  this 
  Journal, 
  3d 
  ser., 
  vol. 
  xxxi. 
  

   ^° 
  Zeitschr. 
  d. 
  d. 
  Geol. 
  Ges., 
  xxiii, 
  1871. 
  

  

  " 
  J. 
  W. 
  Judd, 
  Quart. 
  Jour. 
  Geol. 
  Soc, 
  xli, 
  1885, 
  pp. 
  381 
  and 
  

   382. 
  

  

  ^^ 
  H. 
  C. 
  Lewis, 
  The 
  Genesis 
  and 
  Matrix 
  of 
  the 
  Diamond. 
  

   '^ 
  G. 
  H. 
  Williams, 
  Bulletin 
  No. 
  38, 
  U. 
  S. 
  Geol. 
  Survey. 
  

   ^^ 
  W. 
  H. 
  Winchell, 
  Determinations 
  of 
  the 
  Feldspars, 
  Am. 
  

   Geo., 
  vol. 
  xxi, 
  p. 
  31. 
  

  

  '' 
  Mineral 
  Resources 
  of 
  the 
  U. 
  S., 
  18th, 
  p. 
  958. 
  

   '' 
  This 
  Journal, 
  vol. 
  ix, 
  1875, 
  p. 
  327. 
  

   "^ 
  Dana's 
  System 
  of 
  Mineralogy, 
  p. 
  327. 
  

  

  '^ 
  G. 
  Tschermak, 
  Ueber 
  Pyroxene 
  und 
  Amphibole, 
  T. 
  M. 
  M., 
  

   1871-17. 
  

  

  '^ 
  F. 
  Beche; 
  Experimentelle 
  Untei'suchungen 
  iiber 
  die 
  Bildung 
  

   der 
  Minerale 
  in 
  Magma, 
  T. 
  M. 
  M., 
  xviii, 
  p. 
  124, 
  

  

  ^° 
  J. 
  H. 
  L. 
  Vogt, 
  Beitrage 
  zur 
  Kenntniss 
  der 
  Gesetze 
  der 
  min- 
  

   eralbildung 
  in 
  Schmelzmassen, 
  etc., 
  Kristiania, 
  1892. 
  

   ^^ 
  Dana's 
  System 
  of 
  Mineralogy, 
  p. 
  327. 
  

   ^^ 
  See 
  Iddings-Rosenbusch, 
  p. 
  300. 
  

   " 
  E. 
  H. 
  Williams, 
  Jour, 
  of 
  Geol., 
  vol. 
  i, 
  p. 
  176. 
  

   ^^ 
  Dana's 
  System 
  of 
  Mineralogy, 
  p. 
  324, 
  No. 
  8. 
  

  

  