236 FIRST BOOK OF FORESTRY 



fully appreciated is best illustrated by the fact that 

 pianos, sideboards, and other elegant furniture are not 

 covered with sheet metal (as they might very cheaply 

 and effectively be), and that the handsome floors of costly 

 structures are neither painted nor carpeted. 



' 10. Wood is easily and effectively united by the simple 

 process of gluing, so that valuable combinations, whether 

 for behavior, strength, or beauty, are possible. A three- 

 ply veneer board may be not only as pretty but also 

 more serviceable than a simple board of any one of the 

 two or three kinds of wood of which it is composed; and 

 a white-pine door with cherry or walnut veneer is not 

 only fully as handsome as a walnut door, but it is far 

 superior in its behavior, since all shrinking and warping 

 is thereby practically prevented. Iron and steel may be 

 welded ; most metals can be soldered ; but neither of these 

 processes can be compared to gluing in ease of operation. 



So far wood has been regarded only as a material of 

 construction; but while this is perhaps the most impor- 

 tant consideration, the use of wood as a substance which 

 may be altered physically and chemically is far more 

 important than is generally admitted. 



11. The great mass of mankind is warmed and has its 

 food cooked by wood fires. Even in this country to-day, 

 in spite of the great competition of coal, three fourths of 

 all the homes and thousands of manufacturing establish- 

 ments are supplied with heat from wood. 



