33i 



on this point, it is at once obvious to all those familiar with the 

 peculiar physico-chemical phenomenon known as polymerisation, 

 that the properties of the product of the coagulation of the latex, 

 the quality of the india-rubber produced, is not onesidedly deter- 

 mined by the species of the tree furnishing the latex, but is capable 

 of variation between very wide limits. 



3. The nature of this variation must therefore be determined 

 by the physical, but even much more by the chemical conditions 

 observed in the carrying out of the coagulation process. 



4. So far the truth of this has been recognised only in regard 

 to the physical conditions observed, the variation of the quality of 

 the rubber produced due to specific and definite chemical conditions 

 has hardly been recognised yet otherwise than in the crudest 

 fashion, and it certainly has not been made to our knowledge the 

 object of systematic investigation. 



5. These will probably have to be made on the spot so as to 

 render it possible to examine the latex in its virgin condition, as it 

 is highly probable that the preserving agents which have to be 

 added to the latex, in order to render it sufficiently permanent for 

 shipping it to Europe, almost certainly result in differentiating it 

 more or less from the original product. 



C. O. WEBER, 



Extracted from the India- Rubber and Gutta-Percha Trades' 

 Journal. February, ijth, igo2. 



A RUBBER PLANTATION IN GUATEMALA. 



This account of a large plantation of Castilloa is taken from 

 an article in the Journal d' Agriculture Tropicale (No. 9 March, 

 1902) by M. Rene Guerin, and will interest many planters. The 

 plantation belongs to M. JOAQUIM ASTURIAS, and is known as the 

 Finca (hacienda, plantation) El Baul. A large sample of the rub- 

 ber was exhibited at the Paris exhibition and received a gold 

 medal. 



The plantation includes about 50,000 trees of which 30,000, from 

 10 to 15 years old are producing rubber. The soil very copiously 

 watered consists of zones of sand and of black soil. There seems 

 no difference in the appearance and production of the trees on 

 either zone. The trees shed their leaves in March and April, the 

 dry season, when the seeds are ripe. 



All the trees in the plain country furnish regularly a latex of the 

 same quality, but those on the mountain-slopes, which have to stand 

 a drought, give a greater amount of latex in the wet season than 

 in the dry one, but as the latex is less rich in rubber the return is 

 the same. 



Castilloas grown in the plain begin to give seed in the third 

 year. Those grown in the forests, under shade grow more slowly 

 and are at that age scarcely 9 feet tall, but as soon as they get 



