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parts which are almost constantly flooded, named "igapos." It yields 

 plentifully a thin watery latex which is of little value. 



The third variety, the casca preta" grows in those parts where a 

 certain amount of drainage exists, and which form an intermediary 

 zone between the permanently flooded parts and the high land. It is 

 this variety which yields the latex from which the rubber of com- 

 merce is manufactured. 



The latex," or as it is commonly known, the milk" of the tree, is 

 a milky juice contained in special tubes running amongst the other 

 tissues of the plant. These tubes in the case of the Hevea are con- 

 nected, forming what is known as the laticiferous system " The 

 latex is quite different from what is called the " sap,'^ and probably 

 does not play any part in the nutrition of the tree. According to some 

 authorities, it forms a reserve of water to be drawn upon in cases 

 of drought. The actual extraction of latex cannot kill the tree, and 

 the common statement that the trees are " bled" to death is a mistake. 

 As a matter of fact, though trees exhausted, in as much as they will 

 not yield any more latex, are common, actually dead trees killed by 

 overtapping are rarely met with. The latex, as it exudes from the 

 bark is of a dazzling whiteness, resembling milk, which it also resembles 

 in composition, inasmuch as it consists of an emulsion in which 



caoutchouc" takes the place of the " butter" in ordinary milk. The 

 fluid part of the latex consists of water with very small quantities of 

 albuminous matter, organic acids, and phosphates in solution. 



The extraction of the latex, or as it is usually called, the " tapping" 

 of the tree, is effected by making an incision in the bark of the tree. 

 From this incision the latex flows for about three or four hours, after 

 that it stops flowing of its own accord. The incision shou d not pene- 

 trate beyond the bark, which is generally about f inch thick, into the 

 wood of the tree, and for this reason a very small axe, which rapidly 

 thickens, wedge-like from the cutting edge is used, the shape or the 

 instrument preventing its entering too deep. The axe is generally 

 about f inch wide. The custom is to strike wathit a back-handed blow 

 upwards, thus making an oblique cut in the bark. It is probable that 

 a better method would be to use a chisel and mallet and make a V- 

 shaped incision. Recent experiments at Henaratgoda have shown the 

 advantage of this shaped incisi n. 



The incision having been made, a small tin cup of a capacity of 

 about 4 ozs., is affixed just below it to receive the latex as it flows. 

 This is effected by pressing the edge of the cup, which is sharp, into the 

 bark until it geis a sufficent hold to remain Arm. By this met. od, how- 

 ever, a second wound is made in the bark which is injurious No better 

 method has as yet been sugges ed. In some places a uinding groove 

 is cut in the bark of the tree, and by mcdus of a clay breastwork the 

 milk is conducted into a vessel placed at the foot to receive it. This 

 method is found, however, to be very exhausting to the tree and is 

 falling into disuse. The usual mode of tapping is to make an incision 

 with the axe at the height of some 6 or 7 feet from the ground; on a 

 level with that incision and at a distance of some 8 inches, a 

 second cut is made, and so on round the tree. On the next day incis- 

 ions are made just below these and so on day by day until they reach 

 the ground. Incisions are then made on the same plan beginning as 



