154 THE RUBBER TREE BOOK 



divided into quarters. There are systems which do not in- 

 volve this, although, perhaps, they were not known to Mr 

 Gallagher at the time he gave his lecture and published his 

 pamphlet. Such a system is described later on. It might also 

 be added that instead of finding yields fall off after six months' 

 tapping a considerable increase has resulted on many well- 

 known estates where the basal V is regularly employed. 



The half-spiral in the form of one single oblique cut across 

 half the width of the tree is a good method by which to tap young 

 trees for the first time. It is free from one objection which 

 might be urged against basal V tapping, in so far that it does 

 not involve both right and left-hand paring at the same visit, 

 and is therefore more likely to be regularly and well done. 



Later on the trees can be divided into sections, so as to 

 secure a six or eight years' renewal for the bark cut away. 

 The diagram given herewith will serve to illustrate how this is 

 arrived at. 



It will be seen that there is only one section allowed for each 

 year's tapping. It is believed that this one section will give 

 better results, with an every-day tapping, than paring on two, 

 three, four or even five sections would yield. The reason for 

 this statement is given fully a little further on. 



The half-herring-bone system is at present the favourite 

 system of tapping. Carefully executed, with a reasonable 

 number of cuts, three or four, it can be so laid out as to allow 

 for a four-years' period for bark-renewal. Every-day tapping, 

 on one side of the tree only, is the soundest method and gener- 

 ally gives much the best returns. 



Some contend that cuts on two sides of the tree, tapping on 

 alternate days, is a system with at least equal merits; but this 

 is obviously wrong. It interrupts the passage of plant-food 

 through the bast over twice as large an area of bark. It is 

 better to confine the interrupted area to as small a space as 

 possible. For this reason it is better to confine tapping to 

 one quarter- section of the tree, and the half-herring-bone in 

 this way presents advantages over the full-herring-bone 

 system. 



The tapping results on two of the best-known estates in 

 Sumatra are interesting. One tapped both sides of the trees 

 every day, while on the other neighbouring estate two sides of 



