STUDIES OF SEED-PLANTS 



1ST 



suit in the largest number of radial sections showing the 

 pith-rays. 



In some woods the most beautiful sections are tangential. 

 In order to get the greatest number of such sections, such 

 woods are often cut into sheets of veneer by means of a 

 machine with a large knife which cuts an immense shaving, 



FIG. 55. Ordinary sawing of lumber. FIG. 56. Four methods of quarter 

 s l , s 2 , s 3 , slabs removed by cuts 1, sawing. Cuts 1, 2, 3, 4 remove 

 2, 3 ; and followed by cuts 4 boards which are perfect radial see- 

 to 12. tions on surfaces 1 and 3. Then 



each " quarter " is sawed in order 

 5, 6, 7, 8. The method illustrated 

 in "quarter " C is least desirable. 



a continuous tangential section, as the log is revolved on its 

 axis. In this way an entire log can be cut into tangential 

 section. Pieces of the sheet of veneer are then glued on the 

 surface of other and less valuable boards. This method also 

 has the advantage of avoiding the waste of material which 

 results from cutting with saws. 



180. Forestry. The application of scientific principles 

 to the management of forests is known as forestry. Such 

 scientific management has become necessary because the use 

 of tree stems as lumber has greatly reduced the extent of 

 forests ; and in the interest of future supply it is now desirable 



