﻿654 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Cone 
  no. 
  1 
  melts 
  at 
  tlie 
  same 
  temperature 
  as 
  an 
  alloy 
  composed 
  

   of 
  one 
  part 
  of 
  platinum 
  and 
  nine 
  parts 
  of 
  gold, 
  or 
  at 
  1100° 
  C. 
  

   Cone 
  no. 
  20 
  melts 
  at 
  the 
  highest 
  temperature 
  obtained 
  in 
  a 
  porce- 
  

   lain 
  furnace, 
  or 
  at 
  1530° 
  C. 
  The 
  difference 
  between 
  any 
  two 
  suc- 
  

   cessive 
  numbers 
  is 
  20° 
  C. 
  The 
  upper 
  member 
  of 
  a 
  series 
  is 
  cone 
  36, 
  

   which 
  is 
  composed 
  of 
  a 
  very 
  refractory 
  clay 
  slate, 
  while 
  cone 
  35 
  is 
  

   composed 
  of 
  Zettlitz 
  kaolin. 
  

  

  A 
  lower 
  series 
  of 
  numbers 
  was 
  produced 
  by 
  Cramer, 
  who 
  mixed 
  

   with 
  boracic 
  acid 
  the 
  materials 
  already 
  mentioned. 
  Hecht 
  obtained 
  

   still 
  more 
  fusible 
  ones 
  by 
  adding 
  both 
  boracic 
  acid 
  and 
  lead 
  to 
  the 
  

   cones. 
  The 
  result 
  is 
  that 
  we 
  have 
  now 
  a 
  series 
  of 
  58 
  numbers, 
  the 
  

   fusion 
  of 
  the 
  loAvest 
  being 
  710° 
  C, 
  and 
  that 
  of 
  the 
  highest 
  

   1850° 
  C. 
  

  

  As 
  the 
  cone 
  reaches 
  its 
  fusion 
  point, 
  it 
  begins 
  to 
  bend 
  over, 
  and 
  it 
  

   is 
  considered 
  that 
  the 
  kiln 
  has 
  reached 
  the 
  fusion 
  temperature 
  when 
  

   the 
  tip 
  bends 
  over 
  so 
  as 
  to 
  touch 
  the 
  base. 
  

  

  For 
  practical 
  purposes 
  these 
  cones 
  are 
  very 
  successful, 
  though 
  

   their 
  use 
  has 
  been 
  perhaps 
  somewhat 
  unreasonably 
  discouraged 
  by 
  

   some. 
  The 
  full 
  series 
  can 
  be 
  obtained 
  from 
  Messrs 
  Seger 
  and 
  

   Cramer, 
  of 
  Berlin, 
  for 
  1 
  cent 
  each 
  (or 
  about 
  2 
  J 
  cents 
  each, 
  includ- 
  

   ing 
  duty 
  and 
  expressage), 
  or 
  nos. 
  .010-10 
  can 
  be 
  obtained 
  for 
  1 
  

   cent 
  each 
  from 
  Prof. 
  E. 
  Orton 
  jr, 
  of 
  Columbus 
  university, 
  

   Columbus, 
  O. 
  Recently 
  this 
  series 
  of 
  cones 
  has 
  been 
  restandard- 
  

   ized 
  by 
  Seger 
  and 
  Cramer. 
  The 
  new 
  table 
  is 
  given 
  herewith. 
  

  

  