﻿74 
  

  

  Miller: 
  The 
  wood 
  of 
  Machaerium 
  Whitfordii 
  

  

  of 
  demarcation 
  between 
  heartwood 
  and 
  sapwood 
  is 
  irregular 
  both 
  

   in 
  general 
  outline 
  and 
  detail 
  and 
  is 
  Independent 
  of 
  the 
  concentric 
  

  

  w 
  

  

  rings 
  of 
  growth. 
  

  

  The 
  following 
  figures 
  show 
  the. 
  comparative 
  density 
  of 
  heart- 
  

   wood 
  and 
  sapwood 
  after 
  being 
  dried 
  to 
  a 
  constant 
  weight 
  at 
  a 
  

   temperature 
  of 
  1 
  00° 
  C. 
  The 
  greater 
  density 
  of 
  the 
  heartwood 
  is 
  

  

  Fig. 
  I. 
  Plan 
  of 
  cross-section 
  showing 
  four 
  lines 
  of 
  terminal 
  parenchyma 
  limiting 
  

   growth 
  rings; 
  also 
  paratracheal 
  and 
  diffuse 
  parenchyma. 
  

  

  r 
  

  

  due 
  to 
  infiltrations 
  and, 
  especially, 
  to 
  gum 
  deposits 
  in 
  the 
  vessels 
  

   and 
  parenchyma 
  cells. 
  

  

  (i) 
  All 
  heartwood. 
  1.118 
  

  

  (2) 
  Five-sixths 
  heartwood 
  1.108 
  

  

  (3) 
  All 
  sapwood 
  _ 
  ^ 
  g^^ 
  

  

  