The /Supplement to the Tropical Agriculturist 



was formed under the green or under the dry 

 portion of the bark surface. The second case 

 is a curiosity; the mark of the pricker was 

 found in a pad already formed. As Mr. North- 

 way surely does not mean to tell us that these 

 rubber pads are formed of themselves — like 

 sub-cutaneous Hevean boils ! — we would like to 

 know whether his inference was that a knife 

 must already have been at work ? — or had a 

 pricker been over the same bit of bark before ? 

 In conclusion, does Mr. Northway, by his 

 remarks on the third piece of bark, mean that 

 the use of the pricker is not to be recom- 

 meuded for older, but only for young trees with 

 easily pierced bark ? — the pricker being used 

 always as lightly as possible. 



MR. NORTHWAY ON FAULTY TAPPING 

 BY HIS SYSTEM. 

 Explanation of the Robber Pads. 



Deviturai, Ambalangoda, June 6th. 

 SiK, — I received three pieces of bark from an 

 estate — two with pads said to be caused by 

 my system. You can form your own opiniou if 

 you simply look between the pad and bark. In 

 one case you will see the pricker has not gone 

 through the bark at all ! Why ? Because the 

 bark was dead and dry and the pricker could 

 not go through. It has gone through the green 

 bark on both sides of the dry. 



In the other piece of bark, the pricker mark 

 is seen on the outside, and can be distinctly 

 traced to inside the pad itself. This again 

 proves the pad was there at the time of pricking 

 or the pricker marks could not be inside it. 



The other piece of bark, showing pricker 

 marks, is quite natural and will invariably be 

 seen shortly after any pricking done with too 

 much pressure, but in a few months will be 

 completely covered. Now, judging from these 

 bark samples, it would appear the trees have 

 been cleaned months ahead, because it has a 

 hard dry corky coat outside. I would not 

 expect anything else but failure if I tried to 

 work on such a surface. — Yours, &c, 



CHAS. NORTHWAY. 



II. 



Sunnycroft, Ruanwella, June 10th. 



Dear Sir,— With reference to Mr. North- 

 way's letter re pads of rubber under the bark of 

 Hevea trees, as I am the person who sent him the 

 pieces of bark mentioned and as his letter is 

 somewhat misleading, I must ask you for a small 

 space in your paper to correct it. 



1st. In all the boils which I have seen caused 

 by Mr. Northway's system the pad of rubber 

 always lies between the rows of pricks inside 

 the bark; and I have never seen prick marks, on 

 the inside of it next the wood, proving (as Mr. 

 Northway says) that it was there before. 



The pieces of bark I sent Mr. Northway, with 

 pads of rubber on them, were taken from trees 

 which had never been tapped before, but were 

 tapped on his system — some of them six days 

 and others 12 ; and none of them had boils of 

 any sort on their bark before the operations, in 



fact, we watched some of these boils with pads 

 of rubber underneath them grow from day to 

 day until the final stage was reached and the 

 bark, cambium, and wood were in a rotten state 

 caused by the putrefying of the drying latex 

 shut up inside the bark. 



The trees, as Mr. Northway says, were not 

 scraped months before, but one to two weeks 

 before Mr. Northway's system was tried, and 

 in every tree where the bark was examined the 

 prickers went in right to the wood, far too 

 deep— not too shallow as Mr, Northway insin- 

 uates was the case— owing to the corky bark 

 not being all rubbed off. 



In conclusion, I must say that although 

 Mr. Northway thinks that rows of pricks one- 

 sixteenth-of-an-inch deep in the wood of the 

 Hevea tree will do them little or no harm, 

 Mr. Petch and others hold a different opinion ; 

 and it is the impossibility of working care- 

 fully with the blunt pricker— which requires a 

 lot of force to start it and once started goes 

 right to the wood — that is the grave danger. 



It is rather ridiculous the way some people 

 write and run down those who do not believe 

 in Mr. Northway's system; for I can assure you, 

 Sir, that there is not a single rubber planter 

 in the country who would not rather use Mr. 

 Northway's system on account of its simplicity, 

 if only he could level up yield per acre, and 

 level down cost of upkeep of the system and 

 freedom from disease— to the old systems. 



I ask you, Sir : is there any one, Superinten- 

 dent or cooly, who can judge from the out- 

 side of the tree the exact thickness of the bark ? 

 And if not, how is it possible to put in the 

 pricker just the right distance — so that all the 

 latex is drawn out without injury to the wood ? 

 What happens in practice is that either the 

 pricker goes in too far in a thin-barked tree, or 

 else not deep enough in a thick-barked one ; and 

 so the latex cells are not all touched and the tree 

 does not yield satisfactorily. 



I am not against the sharp pricker. I think 

 it a most excellent tool, but it must be used in 

 conjunction with paring, or not at all, —Yours 

 faithfully, 



D. B. WILLIAMSON. 



[We are exceedingly glad that Mr. D. B. 

 Willamson has written this illuminating letter 

 over his own name — as it was, we believe, 

 on Sunnycroft Estate, that the rubber pads 

 resulting from the new tapping system were 

 first discovered, a phenomenon which was first 

 made public in our columns. We are not so 

 much concerned with the initial correction 

 of Mr. Northway's examination of the pads of 

 rubber on the specimens of bark sent down to 

 Deviturai, although the most startling discovery 

 made by that export— that there wore pads 

 already existing before the pricker pierced the 

 bark in some cases— is denied by the Kelani 

 Valley planter. What is more important is the 

 opinion, with which it is difficult to quarrel, that 

 the use of the pricker is dangerous in so far as 

 it is impossible for coolies to judge of the thick- 

 ness of bark and to regulate the depth to which 



