113 



One disadvantage which has been suggested is the diflBculty of 

 distinguishing such crepe from many specimens of ordinary slow 

 curing crepe, except from first latex pale crepe. This is easily 

 surmounted, however, by labelling boxes, as is done at present for 

 different grades and styling the rubber " slab " crepe or some other 

 fancy name. As a disadvantage it is not worth the consideration of 

 either scientific or practical men, to use a distinction to which 

 I object. 



The third method, viz., shipping in the form of dry block, 

 presents one or two advantages, especially from the producer's point 

 of view. In the preparation of dry block, the rubber has to be 

 creped thin, wormed on a special cutting machine, vacuum or hot 

 air dried in this form and then pressed into blocks. Assuming 

 we are leaving the coagulum for seven days, ci*epeing can be carried 

 out on the 8th day and the rubber prepared ready for shipping 

 on the 9th day. A great saving in factory space is thus effected and 

 also in packing space. It is recommended that the blocks be made 

 about 1| to 2 inches thick. Rubber pi*epared in this manner has 

 been examined in our laboi*atories nearly two yeai"s ago and found to 

 give excellent i-esnlts. 



There is, of course, no improvement of quality in such block, 

 the question being entirely one of economics. 



The disadvantages, of course, of preparing the rabber in this 

 form are very similar to those in the case of pi-eparing and 

 shipping as thin crepe, except that drying space and packing space 

 is saved. 



I trust that the facts stated above will, especially at the close of 

 the pi*esent war, when manufacturers are able to rettirn to more 

 normal conditions and to carry out experiments, stimulate further 

 interest on the part both of the producer and manufacturer in a 

 problem which has not only proved very fascinating as a piece of 

 scientific research, but which is, in my opinion of supreme 

 importance. 



It may be useful to state in conclusion that manufacturers have 

 expressed considerable intei*est in the results obtained and on all 

 sides have added confirmation to the results obtained at the 

 Agricultural Department. 



One other fact, to which reference has been made before, in 

 connection with the advantage of preparing " slab " rubber, is that 

 lump or cup and bucket coagulation can be mixed with first latex 

 rabber, since this rubber if left for the matui'ation period befoi-e 

 crepeing is essentially " slab " rubber. This means, therefore, an 

 inci"ease of first grade rubber, and should prove especially valuable 

 on those estates where natui^l coagulation is abnormally great. 



