

THE INDIA RUBBER WORLD 



[September 1, 1915. 



The Story of Gutta Percha — II. 



PHYSK A 



J.ita percha is so generally confused with i 

 irent to those who know both gums. They are 

 both, sure, the pi I • coagulated milk of 



percha in its manufactured state may re- 

 ble hard rubber, but only in appearance. To tin- expert, rub- 

 ber is not as much like gutta percha a- gold i- like platinum. 

 Tin- fact that there arc- scores ol resinous bastard guttas and 

 bastard rubbers of course adds to the populai confusion. 



From the beginning the Malay, wild and partly civilized, lias 

 been the world's gutta percha gatherer. II. elected in the first 

 place to cut down the tree ami lop it of branches "to pri 

 the milk from flowing into the leaves." catching the latex in 

 bamboo tu anul -.hell-.. 



folded leaves, or in bides in the 



id His axe is the p: 

 the oriental equivalent of the 

 machi 



The latex, yellow white, reddish, 

 or even with a brown tinge, flows 

 slowlj and al - only two 



or three pounds of gutta from a 

 ium tree. The gatherer, if he 

 onlj a little, rubs the milk in 

 his hands and as it thickens forces 

 it into a hide in a block of wood. 

 The latex in the vessels is boiled 

 with lime juice or cocoanut oil un- 

 til ii : ites. Just as rubber 

 milk on the Amazon is injured by 

 rain water, so is gutta percha milk, 

 but by reboiling the stringiness dis- 

 appeat - 



The gatherer may add certain 

 clay~. sag, i flour or any cheap 

 adulterant that is in sight, but that 

 is to be expected 



Thus crude gutta — the Gutta 

 Muntah — comes from the native 

 gatherers in many shapes and of 

 many qualities. As there are 

 many varii gutta producing 



trees, there are mixtures that pro- 

 varieties in the 

 lots that come into the bands ,,f 

 the Chinese traders, who s. >rt. 

 value and mix for the market. 



Malays well know the best trees to tap and are able to give 

 -, lie Gutta Taban Merah unadulterated if thej so desire: that is. 

 if the Palaquium gutta is plentiful. If, however, there are only 

 a few of that best of all gutta trees, the) are apt to mix with 

 it the Minjato. the Simpor. the Putih, or even the Susu. In 

 the long run this it not profitable, for the traders are very alert 

 and pay Ii lots, but the gatherer does not care. The 



m the forest varies in color from 

 light brown to a dirty white. There are always bits of bark in 

 it. Hardness and tenacity are its chief characteristics Sofl 

 ened in hot water it becomes plastic, but not sticky. When cooled 

 it regains its hardri letely. Invariably such lots have a 



definite earthy smell. Such would be the products of the Pala- 

 quium gutta. ken wholly or in part from other 

 Palaquium would vary in color, being sometimes almost 

 black on the surface and white within, some quite plastic. 

 friable, ixy, and some wet and 



\ Gatherer's Hoi si aol . 



For years the collection of gutta was in the hands of wild 

 Malays who never saw a white man and rarely saw the Chinese 

 traders t,, whom they bartered their goods. Their method of 

 trading, so it is said, was unique and simple. At certain seasons 

 the gatherer journeyed to the nearest river and deposited his 

 gutta on the bank. The sign of his particular family — a cow, 

 monkey or tiger — molded from gutta, topped the pile. The 

 owner then secreted himself in the jungle and waited. In time 

 came a Chinese trading boat, which stopped, valued the 

 gum and took it away, leaving in exchange cloth, ornaments, 

 knives, or whatever passed current as valuable from the jungle 

 standpoint. This s,,rt of trading lasted for years, and neither 

 the bloodthirsty savage nor the wily Chinese attempted to get 



the best of the bargaining Many 

 such tokens are to be found ill 

 the hands of curio collectors today, 

 and as they are always made of 

 the best gutta. they give a better 

 idea of the gum than do the ordi- 

 nary forest sample-. 



Gutta percha as it comes to the 

 American or European manufac 

 turer is a composition prepared in 

 the Chinese grading and mixing 

 factories in Singapore. It is the 

 result of the mixing of a variety 

 of lots — good, bad and indifferent 

 — so that certain grades are ob- 

 tained. This is done by shredding 

 the various lots, boiling them soft 

 and massing them on rolls similar 

 to mangle rolls. So generally is 

 this practiced that unmixed lots 

 are not to be found on the market. 

 This gutta looks and feels like 

 blocks of corky wood. It is this 

 that appears in the laboratory for 

 examination, as well as in the fac- 

 tory for manufacture. 



Speaking of the gutta mixers. 



the writer visited a Singapore 



"Godown," where mixing and 



grading was done on a large scale. 



The Chinese owners made no ob- 



jection to a careful examination of 



the various lots of good and bad 



that were selected for mixing, but 



when it came to taking photographs they blandly objected, prom- 



ng to do it themselves later and forward prints — which of 



course was never done. 



Pure gutta percha of the highest grade is colorless and almost 

 transparent in thin cuttings, but shows pinkish in cut sheets 

 about 1/5 millimeter thick, against a white surface. It has no 

 taste and almost no odor, except on decomposition. At ordi- 

 nary temperatures it has an appearance similar to that of wood 

 — smooth, extremely tough and only slightly elastic. It may 

 show a tensile strength fi 525 pounds per square millimeter 

 when stretched 50 to 60 per cent. It is pliable, may be folded. 

 twisted, tied or stretched, and may easily be cut with a sharp 

 blade '>r pointed tool. Its elasticity is low. 



In structure it is cellular but impermeable to water, which it 

 absorbs only in the surface cells. The material becomes fibrous 

 « hen pulled out and at 100 per cent, elongation it will support. 

 without breaking, double the force that was required to stretch 

 it. Unlike rubber, it is easily torn by a transverse force The 



