June 1907.] 



343 



Saps and Exudations. 



But withal we moved slowly ; we watched it ; and finally satisfied ourselves 

 that here was a rubber made scientifically and by men of brains, and not by natives, 

 who forced us to buy 20 to 40 per cent of dirt and water. And so we started to use 

 it in fair quantities. The goods looked nice and clean, and we congratulated 

 ourselves. And now what has happeued ? lbs uniformity has all gone, it comes in all 

 shapes and in all shades, its tensile strength is lower than the Africans, it won't 

 cure, some of it is soft, some of it is hard. 



What have our friends iu Ceylon been doing? Experimenting? If so, back 

 to first stages ; they are off the tracks. We made a large batch of cement with it 

 recently and the swell was not more than 25 per cent of what it was formerly, and 

 should he. Then again, we find variations in the same case. Why mix it ? Placing 

 some weak rubber with the ^ood won't do any good ; it only spoils the whole lot. 



For the sake of the Ceylon rubber industry it is to be hoped that growers 

 will come to their senses and stop fooling before it is too late. The fact thatj|a 

 sample of Ceylon rubber looks good does not prove that it is good. We know that 

 to our cost ; all users know it. If the growers plead ignorance of what is required 

 by the manufacturers, let them import a practical man from some manufacturing 

 country. Ceylon Rubber should be just as reliable as upriver fine Para ; why isn't 

 it? 



[This voices a criticism which is being fairly commonly made on East Indian 

 rubbers. Is is fatal to mix qualities. Biscuits and dry sheet, it is now beginning 

 to be realised, though we pointed it out years ago, are practically used for solution 

 only, and there will be a lamentable set-back to rubber growing unless the new 

 " wet-block" proves good for fine work. It seems to be about as good as fine Para, 

 and it is in that direction that hope lies. — Ed. " T. A."} 



RUBBER YIELDING MISTLETOES IN SOUTH AMERICA. 



The following notes on rubber yielding mistletoes of South America are 

 translated from " Tropenpfianzer, for November, 1905. 



Two or more mistletoes of tropical South America have fruits in which the 

 usual viscin around the seed is replaced by a thick layer of sticky caoutchouc 

 emulsion, which serves the same purpose as viscin in the transport of the seeds by 

 birds. This rubber is not contained in latex tubes, and coagulates spontaneously 

 when the fruits are dried. 



The large fruited mistletoe is Loranthus syringaefolius. It grows in tropical 

 Brazil, British Guiana, and Venezuela. In the last-named country the fruit ripens in 

 the last three months of the year. The fresh fruits are § inch long and \ inch broad. 

 In Venezuela it is parasitic on the Ingas, used as shade trees for coffee. These coffee 

 plantations are often at 3,000 feet elevation and this mistletoe has been met with up 

 to 4,600 feet elevation. Its seeds are transported by a very shy, large, wild dove, 

 and so it is not met with near habitations. The Director of the Venezuela railway 

 obtained 1*7 lb. of rubber from 8 lb. of dry fruit, and considered that a yield of 15 per 

 cent, of pure rubber can confidently be reckoned upon. 



An analysis of dry fruits in Berlin gave 15'02 per cent, of pure caoutchouc 

 which vulcanised well and 11*35 of resin. In June 1905, rubber from this mistletoe 

 was priced at from 3s. 2d. to 3s. 6d. per lb. Some trees covered with the mistletoe 

 have produced 2 cwt. of dry fruits in one season. To obtain the rubber, the dry 

 fruits are crushed with mills or stamps, and the fibre, etc., washed away from 

 the lumps of rubber. The unripe fruits may also be crushed between rollers, 

 washed on sieves, and the rubber emulsion in the liquid coagulated by boiling. 

 Loranthus marginatum also contains rubber. Another rubber-bearing mistletoe 



