PARA RUBBER, 



ing and improving tapping knives for use in obtaining latex from 

 Para rubber trees, and the following accounts of some of those 

 implements which are fairly well-known will be of value. 

 The Carpenter's Chisel. 



This was used in the early tapping days, but lias been superseded 

 by more useful tools. Parkin carried out experiments to see " whe- 

 ther incisions made with a stone or cold chisel gave more latex than 

 corresponding ones made with an ordinary chisel, but did not find 

 any appreciable difference in the amount of latex collected from the 

 two kinds of incision on the single oblique pattern." He finally re- 

 commended a' wedge-shaped chisel with a thickness of ,-'*. to J inch , 

 at a distance of \ inch from the cutting edge ; the breadth of the 

 chisel varied from 1 to U inch. 



With the idea of re-opening the wound area without cutting away 

 a large quantity of tissue, several surgical scrapers and planes have 

 been brought forward, but in every case have proved unsatisfactory. 

 They tend to clog the freshly-opened latex tubes. 

 The " Beta Knife." 



The Beta knife, placed on the market by Messrs. T. Christy & Co., 

 is, according to Johnson, a useful instrument ; the length of the blade 

 is regulated by means of a screw to suit the varying thicknesses of the 

 bark of different trees and so prevent its damaging the wood of the 

 tree. 



Golledge's Knife. 



In the accompanying illustration — Plate 7, Series A — it will be 

 seen that this knife consists of a flat piece of steel provided'at the end 

 with a short sharp bevelled V and a cutting groove along the sides. 

 The knife can be used for making cuts from above downwards, be- 

 low upwards, and from left to right or right to left. It can be used to 

 make the original incision and during subsequent paring operations. 

 The illustration on Plate 3, Series D, showing the herring-bone system 

 of tapping, indicates the good work which has been done by means 

 of this knife. 



Holloway's Knives. 



The Holloway tapping knife is an improved V knife pro- 

 vided with movable blades ; the V head is fastened to the handle by 

 two small screws and nuts, and the blade when worn down is easily 

 replaced. 



Holloway has brought out another knife which is essentially pro- 

 vided with a two-flanged and a basal cutting surface. The blade is 

 made of metal and is curved like a hook at the top ; the cutting area 

 is provided with a flange at either side at right angles to the base and 

 all parts can be easily sharpened. The basal cutting surface or 

 either of the angles can be used in making the original incision, and 

 the two angles may be used for paring either from right to left or left 

 to right. The parts are changeable and all operations can be done 

 with one implement. 



