November i, 1905.] 



THE INDIA RUBBER WORLD 



43 



CAUCHO AND "CASTILLOA ULEl" WARBURG. 



By Dr. IVeriKr Escit (Haiitbiiri:)* 



OPINIONS as to the tree yielding the so-called " Caucho," 

 or Peruvian balls, of commerce have heretofore been 

 very much at variance. It was supposed by some that 

 He7'ea, Cameraria latifolia, and Hancornia speciosa 

 yielded the Caucho.t while HenriquesJ cited reasons which 

 made him doubt the existence of either Hancornia or Castilloa 

 on the eastern slopes of the Andes. The recent explorations of 

 Dr. Ule have established beyond a doubt that Hancornia spe- 

 ciosa exists on the eastern slopes of the Andes, in the Amazo- 

 nas district of Brazil, and on an area much larger than hereto- 

 fore supposed ; and, also, that Caucho is obtained from a spe- 

 cies of Castilloa heretofore unidentified. This species was 

 named Castilloa Ulei by Dr. Warburg. § 



In Ule's description of the manner in which raw Caoutchouc 

 is gathered. I notice the singular statement that supposedly the 

 larger part of Caucho, after its separation with a soap solution, 

 is formed into planhas de Caucho— \>xo?iA. fiat cakes, and that 

 some of the caucAeros coagulate the latex by exposure to the 

 air. Rolled up strips of this Caucho are placed on the market 

 as a higher priced sernamby de Caucho. So far as I have been 

 able to inform myself by reading, and by what I have gathered 

 by conversation with presumably informed persons, Peruvian 

 rubber is put on the market principally in the form of balls, in 

 Hamburg and in all other markets. The balls are generally, 

 though not always, in form of lumps wound with strips, giving 

 them a characteristic appearance. The inner part of the ball, 

 on being cut through, shows also a characteristic conglomera- 

 tion of more or less pale layers. This layering is found not only 

 in the Peruvian slabs ; more prominently isthe similarity noted 

 between Peruvian balls and those originating from Castilloa 

 elastica in Ecuador, and Colombian balls and sausages. 



This relationship is not confined only to the superficial ap- 

 pearance but also to the chemical data of washed samples and 

 to the nearly identical rapidity of vulcanization. Further, it is 

 not a single Castilloa species! but it is stated that quite a num- 

 ber exist which furnish the Caoutchouc of this kind. The sim- 

 ilarity is not a new discovery of mine, but is well known in the 

 trade. This is furthermore endorsed by a published statement :*r 

 '• The physical characteristics of Caucho in the main are the 

 same as in the Central American rubbers." 



The statement made by Ule, that \.h^" planhas de Caucho" 

 are formed by simply coagulating the latex with soap and veg- 

 etable juices cannot, on account of the well known appearance 

 of Peruvian slabs, be accepted unconditionally, because, when 

 cut, their resemblance to those of balls is too apparent. About 

 a year ago I had an opportunity to obtain for a rubber factory 

 here a lot of Peruvian balls, which lot contained, besides the 

 normal balls, exceptionally large loaves— a description of which 

 I deem advisable here, to make the reason of their presence 

 more clear. Ule's description of the manner of obtaining 

 Caucho would be in excellent accord with the appearance of 

 these loaves. 



•Translated from Gummi-Zeilung, Dresden. Jahrg. XIX (1905). P. iiiq. 

 t Fran/- Clouth, ** Gummi, Guttapercha und Ralata." Leipzig: 1S99. P. 78. 

 \ " Der Kautsclmk und seine Qiielleo." Dresden : 1899. P. 13. 

 •iCummi-XeituKg. Dresden. Jahrj;. XIX (1905). P. 96s. [Also The India 

 RuDUHR World, May i, 1905. P. 259] 



I f n American dissertations Castilla instead of Castilloa is often used, and the 

 former, it is claimed, is tlic more correct. 



II Henry C. Pearson, " Crude Rubber and Compounding Ingredients." New- 

 York : 1899. P. 13. 



The above mentioned crude rubber firm imports from year 

 to year large quantities of Peruvian balls, but the official of the 

 firm from which I obtained the lot had never, in many years' 

 experience, seen similar loaves in Peruvians, neither in slabs, 

 and others of whom inquiry was made had never known such 

 loaves to exist, which in quality were farsuperior tothe regular 

 Peruvians. The loaves were, in siae and shape, like the ordinary 

 Matto Grosso Pard, possessing also the faint cheese odor of 

 Matto Grosso Para, which after vulcanization changed into the 

 pleasing odor emitted by bread in process of baking. On being 

 washed a loss of 26 per cent, was noted, the compact blocks, 

 which had only small traces of admixed dirt, containing a 

 quantity of water. The cut surface did not show the yellow 

 spots generally found in Matto Grosso Pard. The large black 

 beetles, with their hard shell wings, which cause so much an- 

 noyance in washing, were also absent. The appearance and 

 characteristics of the washed loaf Peruvian were of such simi- 

 larity of Matto Grosso Para as to eliminate all doubt of its be- 

 ing readily worked upas Matto Grosso Pard, even in respect to 

 the more rapid vulcanization which Matto Grosso Para pos- 

 sesses over regular Peruvian. 



It is hardly necessary to mention that this irregular Peruvian 

 consignment found ready takers and that endeavors were made 

 to obtain regular consignments of this fine material, but, to the 

 best of my knowledge these have been in vain. It may also be 

 mentioned that in the same lot were some pieces which had to 

 be designated as slabs ; this seems to me to be of importance 

 in order to judge correctly the matter in question, because it 

 convinces me all the more that the loaves and slabs are not of 

 an identical nature. Slabs are inferior to balls.* The loaves 

 are no doubt much superior tothe best Peruvian balls. 



I would like to meet here the objection made that at limes 

 Peruvian balls possess also pale outer skins. In the first place 

 this occurs rarely, and secondly these skins are materially darker 

 than those of the before mentioned loaves and of Matto Grosso 

 Para. It is most likely that in my large circle of readers these 

 lines will come before the eyes of some one prepared to shed 

 some light on this subject. For the sake of curiosity it may be 

 mentioned here that an English firm— z. ^., its representative- 

 contends that Caucho and Peruvian ballsare not alike, but that 

 Caucho is the prime quality and Peruvian i/itasi & second qual- 

 ity. Of course the poor buyer is expected to believe this and to 

 take without hesitation, at a higher price, " Caucho balls " in- 

 stead of " Peruvian balls.'' 



Like a rare bird, some time ago, a lot of smoked Colombians 

 arrived here— a Ca.f/i'//i?;j Caoutchouc of light yellow-brown color, 

 of pleasant odor, and easy of vulcanization. The Caoutchouc 

 consisted of balls of about 50 kilograms in weight, which 

 seemed to have obtained their shape by having been treated in 

 the same manner as ordinary Peruvian balls — strips of Caout- 

 chouc and some adhering pieces of wood being, like intestines, 

 pressed together, after which the large lumps were sewed in 

 bast mats and smoked like hams. The cut surface of these 

 lumps resembled much the cross section of Peruvian balls, with 

 the difference that in these Colombians the outlines of the sev- 

 eral Caoutchouc strips were light yellow and therefore very in- 

 distinct. No information could be gained from the English 

 importers in regard to this beautiful lot, except that it was just 



* See Henry C. Pearson. P. 13. 



