Reduction Carried too Far.—However desirable it may be to diminish the number of grades, it must be pointed out that diminution and simplification are not necessarily synonymous terms in this matter. It is well known that on estates where the earth-rubber is only brought in at lengthy intervals, say of a week, the resulting crepe is sometimes very tacky. This is only natural, and is due to the prolonged exposure to the sun’s rays. With the improved machinery now at our disposal, and with the increasing attention which will be given to the lower grades in the future, it is possible to prepare from average bark-shavings crepe free from bark, and of quite a good colour. Where trees are not “scrapped” before tapping, there would seem to be no objection to amalgamating the rubber obtained from the bark-shavings with the No. 1 Compound crepe; and it would be a distinct danger and possible loss if this good rubber were to be mixed with earth rubber. The liability of the latter to become tacky is well recognised; and if possible it should be maintained as a separate grade, in which it would be permissible to mix only rubber obtained from actually dry shavings from “scrapped” trees, or heavily-oxidised scraps which have been rejected from other grades.
Sheets.—Broadly there are no fine distinctions to be made at present in the grading of smoked-sheet rubber; it is either No. 1, or if any so-called defect is visible the sheets must be rejected and plainly marked as “off-quality.”
Clippings (trimmings) may either be made into crepe or shipped under their own description.
Rubber Growers’ Association’s Recommendations.—Taking the foregoing arguments into full consideration, it would seem that, strictly speaking, the number of grades cannot be reduced to less than four at present without producing some amount of confusion.
In its handbook,[15] the Rubber Growers’ Association remarks:
“The fewer grades the better, and regularity of each grade is most important.
“The grading should be as follows:
“(No. 1) Fine crepe (or No. 1 sheet), made from the free or liquid latex.
“(No. 2) Clean light brown crepe, made from lumps and skimmings.
“(No. 3) Scrap crepe, made from tree-scrap.