(_b_) The second type of moist glaze is not so difficult to deal with, and may be removed as a rule by washing the sheets when the rubber is otherwise apparently dry.
It appears to be mainly a matter of unsuitable fuel for smoking and of failure to provide adequate ventilation. A large number of estates have been "thinning-out" or are doing so systematically. The logs thus obtained are often used as fuel in the very green stage. The smoke thus generated must be moist, and if the building is entirely closed, this moisture must be deposited eventually upon the rubber and racks. Some estates have surmounted the difficulty by opening up the roof-ridge slightly so as to allow the moisture to escape with some of the smoke; but if the logs from rubber-trees are to be used, they should be stacked in the sun for some time. Even then, preferably, they should not be used alone. A judicious admixture of dead and rotting jungle-timber appears to give very satisfactory results.
VIRGIN SPOTS AND PATCHES.--If the description really indicates the defect it simply means that portions of the sheets are not dry. When cut they exhibit the typical whitish, opaque appearance described as "virgin." It is doubtful whether any rubber put upon the market as No. 1 product nowadays can have this complaint levelled at it. In the extreme case it points to gross negligence on the part of the packer.
Sometimes what are taken to be small spots of "virgin" are really patches of tiny air or gas bubbles. The point can be easily determined by cutting through the patch and examining the cut edges.
SURFACE MOULDS OR MILDEW.--During the last two years, complaints regarding the incidence of "mouldy rubber" (_i.e._, relating chiefly to the presence of mildews on the surface) have become increasingly common.
To judge by the comments of producers, who as a rule never again see their rubber after it leaves the estate, one would infer that the defect is imaginary, and that the complaints are made solely with a view to repudiation of contracts or the general cheapening of an article of commerce. They can often point out, with a certain amount of truth, that there has been no change in the methods of preparation or curing, and that previously there were no complaints.