BOOK XVII. XXII. 99-\xiv. 102 



and berries of ditferent colours growing together. It 

 is also reported that the same thing may be caused by ' 

 a jackdaw when it hides seeds in the holes that are 

 its storehouses. 



XXIII. From this has bcen derived the process inocutation. 

 of inoculation, consisting in opening an eye in a tree 



by cutting away the bark with a tool resembhng a 

 shoemaker's punch and enclosing in it a seed that has 

 been removed from another tree by means of the 

 same tool. This was the method of inoculation used in 

 old davs in the case of figs and apples ; but the method 

 described by Virgil ° is to find a recess in a knot of bark 

 burst open bv a shoot and to enclose in this a bud 

 obtained from another tree. 



XXIV. And so far Nature has herself been our Gmfting; 

 instructor ; but grafting was taught us by Chance, luie7for. 

 another tutor and one wlio gives us perhaps more 

 irequent lessons, and this was how he did it : a 

 careful farmer, making a fence round his house 



to protect it, put under the posts a base made 

 of ivy-wood, so as to prevent them from rotting ; 

 but the posts when nipped by the bite of the still 

 living ivy created life of their own from another's 

 vitality, and it was found that the trunk of a tree 

 was serving instead of earth. Continuing, the sur- 

 face of the wood is levelled off with a saw and the 

 trunk smoothed witli a pruning-knife. Afterwards 

 there is a two-fold method of procedure ; and the first 

 method consists of inserting the graft between * the 

 bark and the wood, as people in former days were 

 afraid of making a cleft in the trunk ; although sub- 

 sequently they venturcd to bore right into the middle 

 and adopted the plan of forcing the graft into the 

 pith itself inside it, inserting only one graft as the 



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