446 LOGGING 



the box, the incision being made about f-inch deep and from 

 I to 2 inches wide. The tool used for this purpose is called a 

 hack and consists of a blade of high-grade steel about 3 inches 

 wide bent into a U-shape. The cutting blade is fastened by a 

 shank and band to a 2-inch handle, from 18 to 24 inches long, 

 on the end of which is attached a 6-pound iron weight to give 

 force to the stroke. A patent hack recently placed on the 

 market can be adjusted to cut any thickness of chip desired, 

 and in addition makes a square cut instead of a concave one. 



The chipper or renter, as he is called, stands squarely in front 

 of the box and by a right-hand and left-hand stroke removes 

 the chip from the face of the tree. The freshly cut surfaces, 

 called streaks, meet just above the center of the box, forming the 

 peak, and extend upward at an angle of about 40 degrees to a 

 line perpendicular to the outer edge of the box. The cut must 

 not penetrate the heartwood, or else the face becomes "dry" 

 and resin ceases to run. The flow from the fresh incisions runs 

 over the scarified face into the box below. It is most vigorous 

 on the first day after chipping and gradually diminishes until 

 the seventh day, when it practically ceases. It is necessary, 

 therefore, to "chip" the trees weekly, approximately thirty-two 

 streaks being made during the first season. Each successive 

 streak increases the distance to the box, and at the end of 

 the first season the scarified face has extended from 18 to 20 

 inches up the tree; the second year the distance is from 36 to 

 42 inches; the third year from 60 to 65 inches; and the fourth 

 year from 80 to 85 inches. 



Recent experiments have shown that a thin streak produces 

 as good results as a thick one, and has the additional advantage 

 that the tree is easier to chip, since the streaks do not advance 

 up the tree to so great a height. 



The practice of running the chipped faces spirally up the tree 

 has been advocated in order to extend the length of time that 

 a tree could be worked readily. Such a plan is not impracticable 

 since the movement of sap is from one cell to another, through 

 pits in the side walls and not straight up and down the tree. 

 This practice however, is not general. 



