Gums, Resins. 



288 



[OCT. 1906. 



would hardly be advisable out there. But there was another point to which 

 Mr. Barnber called their attention, and that was the question of tackiness. Tacki- 

 ness, as they all knew, was their great enemy, and Mr. Bamber had told them that he 

 had reason for believing that it was due to oxidising enzymes and bacteria or fungus 

 of sorts. He did not know whether that had been found out before, or whether the 

 honour rested with Mr. Bamber of having discovered it, but at any rate it would 

 be one of the most important results that they would take away with them from 

 that Exhibition. (Hear, hear.) If tackiness was due to fungus, he took it all rubber 

 would be dealt with in some such way as in the Amazon, either by aseptics or 

 antiseptics. Mr. Bamber had already told them that great cleanliness would prevent 

 tackiness. Another point was the use of antiseptics, and he would like to know 

 whether it is possible to prevent tackiness by adding some creosote. A few 

 days ago he had a talk with Dr. Willis, and he was of opinion that it would be 

 quite possible to use creosote. He (the speaker) would be very glad to hear whether 

 it was possible to do that, and whether any experiment that had been made showed 

 that l'ubber thus treated was inferior or superior to the ordinary article. At the 

 same time they all knew that the rubber as got from Brazil was smoked, and the 

 smoke contained creosote and acetic acid, and this would tend to show that drying 

 rubber with a very fine solution of creosote would be the right thing. At the same 

 time Mr. Bamber had told them that morning that acetic acid, if added in any 

 surplus quantity, had just the opposite effect, and he was sure they would all be 

 obliged if Mr. Bamber would further elucidate these few points. 



FACTORY RUBBER. 



Mr. Bamber said, as regards the question of bacteria and fungi in tacky 

 rubber, he worked that out about a year ago. He sterilised some rubber and 

 inoculated it under very careful conditions with slight traces of tacky rubber. He 

 was by this means able to inoculate a piece of sterilised rubber and the tackiness 

 spread rapidly through it. He also got Dr. Castellani to work with him, and he 

 found certain bacteria, one or two varieties of fungus, growing on the new tacky 

 rubber. He also found, as he had said before, there was an oxidising enzyme present 

 in most cases where the tacky rubber was very bad. As regard the use of 

 antiseptics he has always pointed out that, in his opinion, the rubber factory 

 ought to be as perfectly clean and pure as the best dairy. In going through some 

 of the estates one saw tins and buckets — at least he saw them some time ago, for 

 he had not been recently— soiled, and with putrefying rubber from previous 

 collections coagulated round the sides. He knew from his own experience that the 

 sap in the latex encourages the growth of bacteria. With regard to the use 

 of creosote he thought it would be quite possible, and he would be glad to try 

 it by the addition of alcohol or an admixture with some oil which would 

 not affect the rubber. He did not think it was necessry if there was 

 was perfect cleanliness in the factory ; but one had always to remember in tapping, 

 when new trees were coming in day after day, that in the first tapping they cut 

 through the sap vessels as well as the laticiferous tubes, and thereby got an 

 admixture of sap in the latex with its sugar and other constituents prone to 

 decomposition. He did not think it was absolutely essential to add any creosote 

 or any other antiseptic, though it was not always possible to keep a factory as 

 clean as one would wish. He had seen rubber treated with creosote, and there was 

 no doubt that it was rather stronger, and it possibly had an effect of increasing the 

 toughness. In any case he would be glad to make experiments in that direction. 



TREATING LATEX WITH SULPHUR. 



Mr. Herbert Wright : — There are one or two questions 1 should like to 

 ask Mr. Bamber. With regard to the subject of treating the latex with sulphur 

 compounds, I should like to ask one or two questions. I presume it is essential to 



