PARA RUBBER. 141 



On the mill they prove to be much softer than dry sheet Brazilian 

 Para. They also take the " compound " much more rapidly than the 

 Amazonian variety. To assist in comparing the tensiles obtained 

 from the several brands of Plantation rubber the data are presented 

 in tabular form. The term " Tensile " means the pounds required to 

 break £ in. by } in. in section of the compounded rubber. 



1 i ■! i.<>\ Samples. Other Samples. 



Dorana- Sudu- Kalu- Bukit Pata 

 kande. ganga. tara. Rajah, ling. 



50 121 99 . . 83 97 



77 113 138 .. 115 136 

 88 143 133 .. 104 140 



78 127 121 . . 107 125 



From the above analyses the same journal proceeds to state : (1) 

 " That Ceylon Para when used to denote the Oriental source of fine 

 Para means a grade lacking in uniformity, when the tensile strength 

 is considered ; (2) the curing qualities of Ceylon fine indicate that it 

 has a decidedly slower action than the South American product ; 

 (3) all the Oriental samples are much softer and are less nervous th an 

 the Occidental types." 



Forms of Plantation Rubber. 



Having compared the differences of Plantation and Brazilian rub 

 ber, it now remains to deal with the various forms of the cultivated 

 rubber which are briefly (1) sheet, (2) biscuit, (3) crepe, (4) worm, 

 (5) lace, (<i) flake, and (7) scrap rubber. The illustrations on Plate 

 27, Series A. will show their general appearances. 



In packing Plantation rubber the packages should not exceed 

 one to two cwt. in weight ; a little Fuller's earth can. according 

 to some authorities, be used. It is not advisable to pack the rubber 

 between paper. 



Biscuit and Sheet Rubber. 



The biscuit and sheet rubber are most commonly met with, and are 

 prepared by allowing the latex to set in shallow receptacles, with or 

 without acetic acid, and washing and rolling the cake of rubber which 

 appears at the top. The biscuits are more or less circular and the 

 sheets rectangular in outline. They are sometimes pressed together 

 to form blocks, and the sheets, on account of their shape, lend them- 

 selves to more economic packing than most other forms. 



According to Messrs. Lewis and Peat, there is a tendency for 

 shipments of sheets of rubber to be taken in preference to biscuits, 

 those having a clear amber colour and measuring about 2 feet by 

 1 foot having obtained high prices. Biscuits which were clear and 

 pale amber-coloured also obtained high prices in 1905. 



An adviser to Messrs. Lewis & Peat is of the opinion that biscuits 

 and sheets will have to be abandoned in favour of balls or other 

 forms like those in which fine Para arrives in Europe, as the former 



