256 APPLICATION OF PRINCIPLES. 



of ringing, that of advancing the maturation of the 

 fruit, is practised upon the Zinzibey, or Jujube tree, by 

 merely fixing in the fork of a branch a very heavy 

 stone, made fast with bandages ; its weight forces the 

 branches a little into a horizontal direction, and thus, 

 independently of the pressure it exercises upon the 

 parts it touches, obstructs the free circulation of the 

 sap. 



CHAPTER XIV. 

 OP TRAINING. 



Training is one of the most artificial operations 

 that gardeners are acquainted with, its object being to 

 place a plant in a condition to which it could never 

 arrive under ordinary circumstances. The practice 

 of it forms one of the most complicated parts of the 

 art of horticulture, each species demanding a method 

 peculiar to itself; but the principles on which it 

 depends are few and simple. These will be best con- 

 sidered with reference to the objects the gardener 

 wishes to attain in performing the operation. 



It is probable that the intention of the first gar- 

 dener who trained a tree was to gain some advantage 

 of climate, by placing the tree close to a wall or other 

 screen ; and this is still one of the greatest objects ; 

 partly with a view to guard the flowers in spring 

 from cold, and especially cold winds, partly to expose 



