﻿64: 
  J. 
  M. 
  Davison 
  — 
  Analyses 
  of 
  Kamacite, 
  Tcenite 
  and 
  

  

  Art. 
  IX. 
  — 
  Analyses 
  of 
  Kamacite, 
  Tamite 
  and 
  Plessite 
  from 
  

   the 
  Welland 
  Meteoric 
  Iron 
  ; 
  * 
  by 
  John 
  M. 
  Davison. 
  

  

  The 
  siderolite, 
  which 
  forms 
  the 
  subject 
  of 
  this 
  paper, 
  is 
  

   described 
  by 
  Edwin 
  E. 
  Howell 
  on 
  pages 
  86-87 
  of 
  the 
  Pro- 
  

   ceedings 
  of 
  the 
  Rochester 
  Academy 
  of 
  Science 
  for 
  1890. 
  Its 
  

   analysis 
  gave 
  Fe 
  91*17 
  and 
  JN"i 
  8*54. 
  It 
  is 
  singularly 
  free 
  from 
  

   troilite 
  and 
  schreibersite 
  and 
  thus 
  offered 
  an 
  unusually 
  good 
  

   opportunity 
  for 
  the 
  analysis 
  of 
  its 
  separated 
  nickel-iron 
  alloys. 
  

   On 
  sawing 
  the 
  meteorite, 
  the 
  outside 
  was 
  found 
  much 
  decom- 
  

   posed 
  ; 
  but 
  between 
  this 
  and 
  the 
  compact 
  center 
  was 
  a 
  zone 
  in 
  

   which 
  the 
  oxidation 
  was 
  superficial 
  and 
  confined 
  for 
  the 
  most 
  part 
  

   to 
  planes 
  of 
  contact 
  of 
  the 
  different 
  nickel-iron 
  alloys 
  that 
  form 
  

   the 
  Widmanstatten 
  figures. 
  It 
  thus 
  became 
  possible 
  to 
  separate 
  

   the 
  kamacite 
  and 
  the 
  tgenite 
  in 
  quantities 
  sufficient 
  for 
  analysis. 
  

   The 
  quantity 
  of 
  kamacite 
  used 
  for 
  analysis 
  was 
  gm. 
  0*934, 
  of 
  

   tgenite 
  gm. 
  0*4522. 
  

  

  The 
  physical 
  characters 
  of 
  these 
  alloys 
  differ 
  widely. 
  The 
  

   kamacite 
  is 
  brittle, 
  breaking 
  with 
  a 
  subeonchoidal 
  fracture, 
  and 
  

   is 
  of 
  the 
  color 
  of 
  cast 
  iron. 
  It 
  was 
  coated 
  with 
  a 
  thin 
  film 
  of 
  

   black 
  oxide 
  which 
  had 
  often 
  a 
  resinous 
  luster 
  as 
  if 
  covered 
  with 
  

   lacquer, 
  particularly 
  where 
  the 
  tsenite 
  had 
  been 
  freshly 
  stripped 
  

   off. 
  This 
  oxide 
  is 
  attracted 
  by 
  the 
  magnet, 
  and 
  is 
  probably 
  

   the 
  magnetic 
  oxide 
  Fe 
  3 
  4 
  . 
  Some 
  pieces 
  of 
  kamacite 
  of 
  a 
  

   millimeter 
  or 
  two 
  in 
  thickness 
  were 
  entirely 
  altered 
  to 
  this 
  

   oxide. 
  The 
  kamacite 
  shows, 
  in 
  places, 
  a 
  corrugated 
  surface, 
  in 
  

   some 
  specimens 
  resembling 
  bundles 
  of 
  rods, 
  like 
  the 
  columnar 
  

   structure 
  of 
  hematite. 
  Figures 
  1 
  and 
  2 
  show 
  this 
  columnar 
  

   structure. 
  In 
  the 
  latter 
  the 
  tsenite 
  which 
  closely 
  followed 
  the 
  

   form 
  of 
  the 
  kamacite 
  is 
  laid 
  back, 
  but 
  not 
  detached. 
  

  

  The 
  tsenite 
  has 
  a 
  silvery 
  luster 
  with, 
  when 
  slightly 
  oxidized, 
  

   a 
  tinge 
  of 
  bronze. 
  It 
  is 
  flexible 
  and 
  elastic 
  and 
  fuses 
  on 
  the 
  

   edges 
  in 
  the 
  oxidizing 
  flame 
  of 
  the 
  blowpipe, 
  turning 
  dark. 
  Its 
  

   fusibility 
  seems 
  to 
  be 
  about 
  5. 
  It 
  resists 
  oxidation 
  better 
  than 
  

   the 
  kamacite 
  ; 
  the 
  contrast 
  between 
  its 
  comparatively 
  fresh 
  

   appearance 
  and 
  the 
  dark 
  film 
  covering 
  the 
  other 
  was 
  marked, 
  

   and 
  facilitated 
  their 
  separation. 
  

  

  Both 
  kamacite 
  and 
  tsenite 
  were 
  magnetic 
  and 
  exhibited 
  a 
  

   w 
  T 
  eak 
  polarity 
  which 
  was 
  more 
  marked 
  in 
  the 
  latter. 
  Pieces 
  of 
  

   tsenite 
  floated 
  directly 
  on 
  water, 
  and 
  of 
  kamacite 
  buoyed 
  on 
  a 
  

   cork, 
  arranged 
  themselves 
  in 
  the 
  magnetic 
  meridian 
  ; 
  the 
  tasnite 
  

   promptly, 
  the 
  kamacite 
  after 
  being 
  left 
  for 
  some 
  time 
  protected 
  

   from 
  air 
  currents 
  under 
  a 
  bell 
  glass. 
  The 
  meteorite 
  as 
  a 
  mass 
  

   also 
  showed 
  polarity. 
  The 
  taenite 
  is 
  found 
  separating 
  the 
  plates 
  

  

  * 
  Read 
  before 
  the 
  Rochester 
  Academy 
  of 
  Sciences 
  and 
  published 
  in 
  the 
  Pro- 
  

   ceedings 
  for 
  1891, 
  where 
  it 
  is 
  accompanied 
  by 
  a 
  plate, 
  not 
  reproduced 
  here. 
  

  

  