EXERCISE 8 



ORNAMENTAL CHARACTERISTICS OF OAK WOOD 



Materials. Cross sections of an oak log about three inches in 

 diameter, as used in Exercise 7 ; a section of a seasoned white oak log 

 about four or five inches in diameter and six inches long or longer. 



Directions for work. With the cross sections of wood in 

 your hands identify pith, heartwood, sapwood, annual layers, 

 medullary rays, inner bark, and outer bark. Note whether 

 the specimen represents a slow-growing or a rapid-growing 



species. Is it ring-porous or 

 diffuse-porous ? 



Cut a section five or six 

 inches long from the larger 

 log and saw lengthwise into 

 boards about one-half inch in 

 thickness. Smooth both sides 

 of these boards with a plane 

 and sandpaper. The sawing 

 and rough planing should be 

 done on the power saw and 

 planer in the school shops 

 if the school possesses such 

 machinery. 



One or two of these boards will show surfaces that are 

 nearly parallel with the medullary rays. These correspond with 

 " quarter-sawed oak." Find these boards and mark them. In 

 the remainder of the boards the surfaces are tangential to the 

 annual layers. They may be called " plain-sawed " boards. 



Identify sapwood, heartwood, medullary rays, and wood 

 pores on the planed surfaces of each board. Describe each 

 of these clearly enough for purposes of identification by a 

 beginner. 



Determine the relation of the structural elements of the wood 

 mentioned above to the appearance of the wood in finished 

 furniture in the following manner. Treat one plain-sawed sur- 

 face with linseed oil, a second with a dark wood-filler, and a 



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