August i, 1905.] 



THE INDIA RUBBER WORLD 



365 



A NFW SOURCE OF AMAZON RUBBER. 



By Louis //. Ayme, United Slates Consul at Pard* 



I^HE India-rubber exported from Para has been traced to 

 four main sources: India-rubber proper from the 

 Hevea Brasiliensis ; " caucho " from the Castilloa elas- 

 tica or a closely allied species, Castilloa Ulei ; " mani- 

 5oba " from the Manihot Claziovii, and " mangabeira " from 

 • the Ilancornia speciosa. 



It has long been known that the latex of other trees is some- 

 times mixed with the latexoi thcHevea, giving inferior products 

 more or less readily recognizable. But from the last bulletin 

 of the state museum (Museu Goeldi) it appears that a very con- 

 siderable part of the India-rubber of commerce known as" fine 

 Para," and which has always been supposed to be the exclusive 

 product of the Hevea Brasiliensis, is really from a new and 

 hitherto unsuspected source, a tree of the genus Sapium, of the 

 family of the EnphorbiaceiT. The honor of this discovery rests 

 with Professor Henri Jumelle, who learned his facts from a Mr. 

 Bonnechaux, a French explorer, and published a long account 

 thereof in 1903. Dr. J. Huber, the eminent botanist of the Mu- 

 seu Goeldi (Para), who has personally explored the Amazon, 

 even in its remote headwaters, has succeeded in identifying the 

 tree, and has written a most interesting report, in which he in- 

 cludes Professor Jumelle's article, and which I have translated 

 in extenso as an appendix to this report. I have also had sev- 

 eral interviews with Dr. Huber, and have examined the two 

 small specimens of pure "tapurii " rubber, and also the many 

 growing trees of Sapium in the botanic gaidens. 



Dr. Huber has also been kind enough to furnish me with a 

 number of specimens of the leaves of several varieties of Sapium, 

 together with a letter in which he refers to an entirely new tree, 

 the " Burra leitera." These specimens and a copy and transla- 

 tion of Dr. Huber's letter are sent with this report. 



The new source of rubber appears to have been precisely iden- 

 tified by Dr. Huberas Sapium aiicuparium (Jacquin). The tree 

 bears many native names — " taputii," " murupita," " curupita," 

 etc. It is of the family of the Euphorhias, of which the Herea 

 is also a genus, although widely separated. 



A salient characteristic of the Sapium seems to be its poly, 

 morphism. Dr. Huber showed me a specimen which had borne 

 very large, long leaves. It was transplanted to a shady place, 

 and at once began to put forth small leaves not above one- 

 fourth the size of the former leaves and of an entirely diflerent 

 form. Leaves of both kinds were growing on this tree, although 

 the large leaves were disappearing. From Dr. Huber's experi- 

 ments and observations it would seem that the same tree will as- 

 sume widely different aspects under varying circumstances, the 

 main controlling factors being sun, shade, dry ground, and wet or 

 periodically inundated ground. Dr. Huber finds that the Hez>ea 

 is similarly polymorphous, and asserts that the so-called 

 "black" and "white" varieties are really one and the same 

 tree, the " black " growing in the shade and farther from the 

 water, and the " white " growing on the edges of the forest near 

 water and exposed to the sun. This question of polymorphism 

 becomes important, if, as seems probable, the quality and quan- 

 tity of latex is similarly variable. 



According to Mr. Bonnechaux the rubber from the "tapurfi" 

 trees exclusively can not be distinguished from pure Hevea rub- 

 ber. But there is testimony to the effect that pure " murupita" 

 rubber (which seems to be identical with" tapuiii rubber) is less 

 * An official report published at Washington. 



elastic and less resistant to traction than Hevea rubber. Mr. 

 Bonnechaux says that the merchants of Europe have never 

 made any complaints. This is by no means certain. If com- 

 plaints were made the commission houses of Para and Mandos 

 would not make them public, but would merely refrain from 

 purchasing the special grade of rubber complained of. Further, 

 I find that there are sold in this market considerable quantities 

 of a rubber which comes, for the most part, from the upper 

 Xingii river, and which is known as "borracha fraca,"*or " weak 

 rubber," which resembles closely in appearance and quality the 

 specimens of "murupita" or " tapurii " rubber in the Museu 

 Goeldi, Pard. A price between that paid for "entrefina" and 

 " sernamby " is paid for this rubber, showing that it is known 

 to be of inferior quality. It is popularly supposed that it is 

 made from Hez'ea latex mixed with " bastard rubber." What 

 this last is does not seem to be known. In my opinion this 

 " borracha fraca " is " tapurii " rubber. 



But there seems to be doubt that large quantities of " tapuii'i" 

 latex are mixed with Hevea latex, possibly to the extent of 40 

 per cent., without any difference in quality resulting, and it is 

 even questionable to-day whether pure rubber, made exclusive- 

 ly from the latex of Heveas, is sold in any considerable amount. 

 I have had some inquiries made for me in the market with 

 rather startling results. A small quantity, a ton or so, of Up- 

 river rubber was offered. A very low price was tendered, and 

 to the expostulation that ensued the buyer replied : 



" I can not offer more. This rubber is one-half ' murupita ' 

 rubber." 



Quick as a flash the statement came : " No, indeed, sir ; this 

 is pure rubber. Farther down the river they do mix it, but this 

 is pure." 



The experiment has been tried several times and always 

 brings the same response, a denial of any mixing in the particular 

 rubber offered, but an acknowledgment that such mixing does 

 occur. Now, I am informed that the "borracha fraca," which 

 is probably pure "tapuiii rubber," is sold in the New York 

 market for about the price paid for good " entrefina." All of 

 which results in this : That there is produced from the latex ol 

 Sapium aucuparium (Jacquin) a rubber which finds ready sale 

 and which, when mixed with Hevea latex, produces a rubber not 

 to be distinguished from " borracha fina," or the supposed pure 

 Hevea rubber. The expression used by a very prominent buyer 

 here with whom I have discussed this matter is; " If there is 

 such a thing as pure Hevea rubber. 



This Sapium is a rather hardy tree. It grows with great ra- 

 pidity. There is a tree in the botanic garden here 5 years old 

 from seed, which is fully 8 inches in diameter 3 feet above ground 

 and may soon be tapped. The seeds are small and apparently 

 very hardy. They are certainly much less delicate than Hevea 

 seeds, as Dr. Huber planted seeds which were more than 6 

 months old which gave strong, healthy plants. Mr. Bonne- 

 chaux speaks of an es/rada of 140 "tapurii " trees, and from his 

 data it is calculated this estrada yields about one-half a ton of 

 rubber annually. The " tapurii " is said, however, to be deli- 



* Under date of May 31, 1905, Consul .\yme writes: "I have secured a good 

 specimen of the ' borracha fraca,' referred to in my report of May 25 as com- 

 ing from the upper Xingii river. The present specimen is from the Tapajos 

 river, but is, I believe, the rubber produced by the ' tapurii ' or Sapium aucupa- 

 rium. For comparison I send two specimens of the supposed llevea product, 

 " tina ' and * sernamby.' '' 



