﻿CHAPTER 
  VIII 
  

   TIMBER; 
  FORESTRY 
  

  

  100. 
  Wood 
  as 
  a 
  structural 
  material. 
  1 
  There 
  are 
  a 
  few 
  dis- 
  

   advantages 
  in 
  the 
  use 
  of 
  wood 
  for 
  many 
  purposes 
  of 
  construc- 
  

   tion. 
  Wooden 
  fences 
  and 
  buildings 
  are 
  easily 
  destroyed 
  by 
  

   fire. 
  Wooden 
  posts, 
  bridges, 
  and 
  similar 
  structures, 
  and 
  shin- 
  

   gled 
  roofs, 
  are 
  subject 
  to 
  rather 
  rapid 
  decay. 
  Most 
  woods 
  

   will 
  not 
  stand 
  long-continued 
  friction 
  without 
  wearing 
  out, 
  

   so 
  that 
  many 
  of 
  the 
  working 
  parts 
  of 
  machines, 
  when 
  made 
  

   of 
  wood, 
  as 
  they 
  often 
  were 
  by 
  the 
  early 
  settlers 
  in 
  this 
  

   country, 
  were 
  short-lived. 
  

  

  Some 
  of 
  the 
  advantages 
  of 
  wood 
  for 
  constructive 
  purposes 
  

   are 
  as 
  follows 
  : 
  

  

  1. 
  Wood 
  is 
  far 
  cheaper 
  than 
  metals 
  ; 
  bulk 
  for 
  bulk, 
  it 
  does 
  

   not, 
  on 
  the 
  average, 
  cost 
  more 
  than 
  one 
  thirtieth 
  as 
  much 
  as 
  

   iron 
  or 
  steel. 
  

  

  2. 
  Wood 
  is 
  much 
  more 
  easily 
  worked 
  than 
  metals. 
  

  

  3. 
  Weight 
  for 
  weight, 
  some 
  wood 
  is 
  stronger 
  than 
  iron 
  or 
  

   steel. 
  A 
  bar 
  of 
  hickory 
  will 
  stand 
  a 
  stronger 
  pull 
  lengthwise 
  

   than 
  one 
  of 
  wrought 
  iron 
  of 
  equal 
  length 
  and 
  weight. 
  A 
  block 
  

   of 
  the 
  best 
  hickory 
  or 
  long-leaf 
  pine 
  will 
  bear, 
  without 
  crush- 
  

   ing, 
  a 
  greater 
  load 
  than 
  a 
  block 
  of 
  wrought 
  iron 
  of 
  the 
  same 
  

   height 
  and 
  weight. 
  

  

  4. 
  Wood 
  is 
  light 
  and 
  is 
  therefore 
  much 
  more 
  convenient 
  

   than 
  metals 
  for 
  many 
  purposes 
  of 
  construction, 
  as 
  building 
  

   vehicles 
  and 
  making 
  packing 
  cases 
  and 
  tool 
  handles. 
  

  

  5. 
  Wood 
  is 
  a 
  poor 
  conductor 
  of 
  heat 
  and 
  on 
  this 
  account 
  is 
  val- 
  

   uable 
  in 
  the 
  construction 
  of 
  houses, 
  railway 
  cars, 
  refrigerators, 
  

  

  1 
  See 
  Roth, 
  First 
  Book 
  of 
  Forestry, 
  pi>. 
  :W2-:238. 
  Ginn 
  and 
  Company, 
  

   Boston. 
  

  

  107 
  

  

  