﻿Plessite 
  from 
  the 
  Welland 
  Meteoric 
  Iron. 
  65 
  

  

  of 
  kamacite 
  and 
  enveloping 
  the 
  crystals 
  of 
  plessite. 
  Figures 
  3 
  

   and 
  4 
  show 
  plates 
  of 
  kamacite 
  which 
  were 
  in 
  close 
  contact, 
  and 
  

   when 
  separated 
  were 
  found 
  to 
  have 
  been 
  joined 
  by 
  a 
  little 
  

   triangular 
  prism 
  of 
  the 
  same 
  substance. 
  

  

  It 
  was, 
  at 
  first, 
  intended 
  to 
  analyze 
  the 
  plessite 
  as 
  a 
  whole; 
  

   but 
  on 
  examination 
  its 
  line 
  layers 
  were 
  so 
  suggestive 
  of 
  kama- 
  

   cite 
  and 
  tseriite 
  that 
  the 
  attempt 
  was 
  made 
  to 
  separate 
  them, 
  

   and 
  to 
  analyze 
  each 
  separately. 
  It 
  way 
  found 
  that 
  one 
  was 
  

   brittle, 
  the 
  other 
  flexible 
  and 
  elastic 
  ; 
  one 
  dark 
  with 
  superficial 
  

   oxidation, 
  the 
  other 
  showing 
  the 
  tsenite 
  luster. 
  Physically 
  

   their 
  correspondence, 
  the 
  one 
  with 
  kamacite, 
  the 
  other 
  with 
  

   taenite 
  was 
  exact, 
  and 
  in 
  the 
  kamacite-like 
  part 
  the 
  columnar 
  

   structure 
  was 
  shown 
  on 
  a 
  diminutive 
  scale, 
  the 
  diameter 
  of 
  the 
  

   rods 
  being 
  from 
  \-\ 
  mm. 
  

  

  Their 
  separation 
  then 
  became 
  simply 
  a 
  matter 
  of 
  patience, 
  

   and 
  with 
  the 
  aid 
  of 
  a 
  watchmaker's 
  glass, 
  and 
  a 
  magnetized 
  

   needle 
  to 
  pick 
  up 
  the 
  grains 
  and 
  flakes, 
  most 
  of 
  which 
  were 
  too 
  

   small 
  for 
  even 
  delicate 
  forceps 
  to 
  handle, 
  there 
  was 
  obtained 
  

   for 
  analysis, 
  of 
  the 
  part 
  resembling 
  kamacite 
  gm. 
  0*5261, 
  of 
  

   that 
  resembling 
  tasnite 
  gm. 
  0*1314. 
  The 
  thickness 
  of 
  the 
  

   kamacite 
  was 
  from 
  1-2 
  mm., 
  that 
  of 
  the 
  tsenite 
  from 
  ^"A 
  

   mm. 
  In 
  the 
  plessite 
  the 
  kamacite-like 
  bands 
  were 
  from 
  -J-J- 
  -^ 
  

   mm. 
  thick 
  ; 
  the 
  taenite-like 
  bands, 
  as 
  nearly 
  as 
  could 
  be 
  meas- 
  

   ured, 
  from 
  ||o-iii 
  mm 
  - 
  

  

  The 
  method 
  of 
  analysis 
  was 
  the 
  same 
  in 
  each 
  case. 
  The 
  

   material 
  was 
  gone 
  over 
  repeatedly, 
  piece 
  by 
  piece, 
  with 
  a 
  

   watchmaker's 
  glass 
  and 
  very 
  carefully 
  assorted 
  and 
  cleansed, 
  

   the 
  pieces 
  of 
  kamacite 
  being 
  scraped 
  bright. 
  It 
  was 
  not 
  possi- 
  

   ble 
  to 
  do 
  this 
  to 
  any 
  extent 
  with 
  the 
  kamacite-like 
  part 
  of 
  ples- 
  

   site. 
  It 
  was 
  dissolved 
  in 
  dilute 
  hydrochloric 
  acid 
  by 
  the 
  aid 
  of 
  

   a 
  weak 
  galvanic 
  current, 
  at 
  the 
  positive 
  pole 
  of 
  the 
  battery. 
  

   The 
  carbon 
  thus 
  separated 
  was 
  collected 
  on 
  a 
  G-ooch 
  filter 
  and 
  

   burned. 
  The 
  nickel 
  and 
  cobalt 
  were 
  separated 
  from 
  the 
  iron 
  

   by 
  digestion 
  in 
  ammonium 
  hydrate, 
  the 
  process 
  being 
  repeated 
  

   four 
  times. 
  The 
  iron 
  was 
  weighed, 
  and 
  the 
  nickel 
  and 
  cobalt 
  

   first 
  determined 
  together 
  by 
  electrolysis, 
  then 
  separated 
  by 
  

   potassium 
  nitrite 
  and 
  each 
  determined 
  separately 
  in 
  the 
  same 
  

   manner. 
  For 
  comparison, 
  the 
  analyses 
  of 
  kamacite 
  and 
  tasnite 
  

   are 
  given 
  each 
  next 
  to 
  its 
  corresponding 
  part 
  of 
  the 
  plessite. 
  

  

  Kamacite. 
  

  

  

  Plessite. 
  

  

  

  Tasnite. 
  

  

  

  Kamacite-like 
  part. 
  

  

  Tasnite 
  -like 
  part. 
  

  

  

  Fe 
  93-09 
  

  

  92-81 
  

  

  

  

  72-98 
  

  

  74-78 
  

  

  Ni 
  6-69 
  

  

  6-97 
  

  

  

  

  25-87 
  

  

  24-32 
  

  

  Co 
  '25 
  

  

  •19 
  

  

  

  

  •83 
  

  

  •33 
  

  

  C 
  -02 
  

  

  •19 
  

  

  

  

  •91 
  

  

  •50 
  

  

  100-05 
  100-16 
  100-59 
  99-93 
  

  

  