The other alternative is to trim the ends when the bulk of the rubber is thoroughly smoke-dried. The moisture containing portions are then returned to the smoke-house until dry, and are subsequently packed without further treatment as “smoked-sheet clippings.” It will be plain that, except in the particularity of form, these clippings differ in no degree from the original sheets; and, owing to extra smoke-curing, may arrive in even better condition. One must be prepared, however, to find that a slightly lower price is offered. Whether the price obtained would be comparable with that commanded by the crepe made from wet sheet slipping would depend upon general ruling market conditions, and the degree of care exercised in guarding against the inclusion of any inferior pieces of rubber. In ordinary factory practice, there could be no room for abuse under the latter clause.
Other Infrequent Defects.—This chapter will be closed with a reference to other small defects which, although infrequent, cannot be classed as minor complaints. In point of fact, when they occur, they assume an importance, in the eyes of the consumer, which is not, perhaps, sufficiently appreciated by producers.
Dirt.—Trouble from this source should be absent, but carelessness on the part of packing coolies may be responsible for occasional complaints. How the dirt is incident may remain a mystery, but it has been noted that sheets have at times been thrown upon a cement floor. A certain amount of loose dust may thus adhere to the rubber.
Ash.—The source of this surface deposit scarcely needs indication. Where open-hearth furnaces are employed, and the wire-mesh floor screens are not perfectly sound, fine ash may find its way into the upper chamber. If this trouble is persistent in spite of precautions, the sheets should be surface-washed and air-dried before packing.
Bark.—Complaints of the presence of particles of bark in sheet rubber used to be fairly frequent, but are now less common. The trouble may be traced to the use of defective straining sieves when the latex is being handled.
Splinters.—The use of packing-cases of unplaned soft timber is responsible for complaints of this nature on delivery. Without here discussing the larger question of the ideal packing case, it is sufficient to emphasise that the interior surfaces of wooden chests should be planed. The cases are often so damaged in transit, that splinters of wood may be found throughout the contents. The device adopted on some estates may go far to prevent this. The cases are first lined with loose sheets, and finally other sheets are arranged to overlap at the top of the case. The bulk is thus enclosed in a wrapping of sheets, and any splinters or other deleterious substances are confined to the surface of the mass.