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mentioned. In less than two minutes the whole of the diluted 

 latex had run through the wire sieve into the bottom vessel, and 

 so far as the object for which the machine was intended (i.e.) the 

 separation of the globules of Caoutchouc that are held in suspen- 

 sion in the latex was apparently a failure. Why it was a failure 

 I am not quite sure. What appeared to us to be reasons were 

 that either the blades did not revolve with sufficient rapidity, or 

 that the meshes of the wire sieve were too large, which I hardly 

 think could be the case, for they were as close as fine muslin; be 

 that as it may, it seemed that before the revolving blades had time 

 to act on the latex it had all run through the sieve into the recept- 

 acle below. The appearance of the latex looked at from above 

 was slightly frothy, but the consistence after an hour was appa- 

 rently of equal density all through as tested by the feel of the 

 water drawn off from the tap, and comparing it with the upper 

 surface. Mr. BlFFEN who was the first to try and separate the 

 rubber by centrifugalization says that some latices require a 

 greater number of revolutions than others — 9,000 per minute for 

 Para whilst Castilloa separates readily at 1,000 revolutions per 

 minute less. Unfortunately we had no time to wait any longer, 

 we therefore took the latex in the machine to Malacca, and coagu- 

 lated it in a manner, I shall presently describe. One cannot say 

 much from this single trial of the machine for or against it — the 

 principle is alright and I have no doubt that after a few experi- 

 ments one would be able to use it with practical effect. One must 

 remember that it is a washer and separator, and not a coagulator, 

 and the difference between the two processes is this: — In coagula- 

 tion a mass of rubber is obtained which cannot be again mixed up 

 with water. In separation on the contrary, the particles have not 

 been fused together, but still preserve their individuality, and the 

 cream they form can be again mixed up with water to produce as 

 it were latex again. Further trials are necessary with the machine 

 which can alone prove whether it is suitable for Rambong latex 

 or not, for while it may be suitable for Castilloa owing to the 

 globules of Caoutchouc being larger, and separating more readily 

 than others; it may require some modification to make it suitable 

 for Rambong and Hevea latices. 



I now turn to another interesting point, viz., the method of 

 tapping; and the amount of latex produced from a certain number 

 of trees. As regards the method of tapping, we tried a new kind 

 of tapping knife invented by Mr. Tan Chay Yan, which consisted 

 of a chisel-like blade being fixed at an angle into a brass socket 

 head and regulated by means of screw nut, as to the depth of the 

 incision. — The makers had not quite carried out their instructions, 

 inasmuch as the blade was far too wide (about \ inch) and the 

 cutting edge was not shaped properly, and so we had to fall back 

 on ordinary pocket knives. The bark of these young Rambong 

 trees is however, so soft, that a good knife is a very good tool for 

 making the incisions. As regards the shape of the incisions we 

 began by making the well known vertical grove with oblique 

 shaped cuts running into it. It was quickly observed that the 



