﻿cm 
  

  

  iifii 
  

  

  So 
  much 
  of 
  the 
  wood 
  work, 
  in 
  all 
  these 
  constructions, 
  

   as 
  may 
  be 
  exposed 
  to 
  the 
  air, 
  and, 
  particularly, 
  such 
  

   parts 
  as 
  are 
  subject 
  to 
  the 
  alternate 
  action 
  of 
  the 
  air 
  and 
  

   water, 
  are 
  liable 
  to 
  more 
  or 
  less 
  rapid 
  decay, 
  and 
  should 
  

   be 
  protected 
  by 
  thick 
  coatings 
  of 
  paint, 
  or 
  other 
  preser- 
  

   vative 
  material. 
  Such 
  other 
  parts 
  as 
  are 
  imbedded 
  in 
  the 
  

   embankment, 
  however, 
  will 
  be 
  found 
  to 
  last 
  for 
  years. 
  

  

  