14 



VEGETABLE SUBSTANCES. 



Cork Oak Quercus suber. 



second, which is removed about ten years after, is 

 also of an inferior quality. After this, the operation 

 is repeated once in eight or ten years, the produce 

 being greater hi quantity, and superior in quality, 

 each successive time. According to Duhamel, a cork- 

 tree thus barked will live a hundred and fifty years. 

 The months of July and August are those which are 

 chosen for removing the cork. The bark is cleft 

 longitudinally, at certain intervals, down to the 

 crown of the root, with an axe, of which the handle 

 terminates in a wedge ; and a circular incision is 

 then made from each extremity of the longitudinal 

 cuts. The bark is then beaten, to detach it from the 

 liber ; and it is lifted up by introducing the wedged 

 handle, taking care to leave sufficient of the inner 



