243 



KOALATEX IN RUBBER COAGULATION. 



Hamburg, Hoppensack, 8. 



There exist several methods for the transformation of proto- 

 rubber, which finds itself in each rubber milk, into rubber. Even the 

 best rubber milks do not give good rubbers, if a bad method of 

 preparation or a non-practicable coagulator has been used. All 

 rubber milks contain a bigger or small proportion of foreign sub- 

 stances, which, partly, may be easily removed. The most trouble 

 is caused by the albuminoid matters which accompany the proto- 

 rubber and, if not carefully removed, cause fermentation, overheating 

 and a bad smell of the rubber. In fact it is very difficult to remove 

 quantitatively the albuminoid matters even from Hevea rubber milk. 

 Therefore it is necessary to use as coagulators only such chemicals 

 as have a high disinfecting and preserving action. Liquid acids as 

 sulphuric, hydrochloric and -acetic acid are not practicable for use 

 of plantations which mostly do not have good communications, and 

 the transportation of these liquid acids is very dangerous and costly. 

 Besides, these acids have nearly not at all any disinfecting or pre- 

 serving value, and they do not prevent the becoming black of some 

 kinds of rubber, especially after drying. There exists some organic 

 acids which have not only a good coagulating action, but also have 

 the superiority of being efficacious disinfectors and preservators, but 

 their prices are extremely high. Owing to the far-seeing examina- 

 tions and experiments of a highly prominent crude rubber expert 

 the rubber coagulation problem had been solved by the compound 

 " Koalatex," which is a good acting coagulator, gives light coloured 

 rubbers, which remain light after being dried. Koalatex prevents 

 must, is easily transportable and safe, and has a low price, '$19.50 

 per 100 lbs. or £4.10.0 per cwt. f.o.b. Hamburg, package included, 

 in tins and cases. 



LEHMANN and VOSS, 



Manufacturing Chemists. 



PARA RUBBER IN SAMOA. 



In the Consular Report for Samoa for 1905 is the following 

 account of rubber planting in Samoa. Mr. T. Andrew, a planter, 

 reports — " In 1904 I supplied your yearly report with a few remarks 

 on the cultivation of Hevea brazil iensis in Samoa. Since then the 

 trees have grown rapidly, not so much in height as in girth, they 

 are just six years old from the seed, measuring 25 consecutive trees 

 at three feet from the ground, the largest tree measured 24^ inches 

 in circumference; the average of the whole was 17^ inches. The 

 measurements are by no means insignificant when compared with 

 those made at the experimental gardens of the different districts 

 within the zone of rubber culture. The trees in question are planted 



