Providing that the coagulated lump is free from bark, leaves, and leaf-stems, and certain other precautions taken, the difference in price between coagulated-lump crepes and first-grade crepes should be very slight. Too often, however, not sufficient supervision is given to the coagulated-lump rubber, and it is common to see it come into the factory containing leaves and bark. These should be picked out before the latex is strained, but obviously it would be better to ensure that they did not enter the buckets in the first place. It would seem reasonable to suppose that if some means could be employed for preventing or checking the surface oxidation of naturally-coagulated lump rubber, there would be a corresponding improvement in the colour of the dry crepe. That such a method is practicable has been demonstrated on many estates. The lump when lifted out of the latex is allowed to drain for a few minutes, and is then (without squeezing) placed in a dilute solution of sodium bisulphite. A 1 per cent. solution is sufficiently powerful. It is not to be thought for a moment that by the use of sodium bisulphite any previous oxidation will be counteracted; all that is claimed for the treatment is that any further surface oxidation will be checked, and the rubber may be allowed to remain until the next day, for working, if it is so desired. It will probably be found that quite a quantity of latex has been expressed from the lumps by contraction, and acid may be added to obtain the rubber from this. On other estates the lump rubber is worked on the machines as it is received, and the resulting crepe is submerged in a weak solution of sodium bisulphite over-night. It is then rinsed in water and hung to drip before weighing and placing in the drying house. Under certain conditions some of the lump rubber darkens rapidly during transport to the store, and any such oxidised portions must be rejected if a uniform colour is to be expected in the crepe. Following the procedure indicated above, some estates find it possible to prepare from naturally coagulated lump rubber a crepe which can be classed as No. 1 grade. SKIMMINGS AND WASHINGS.--The skimmings of tanks, as already shown, may be prepared sometimes as a second quality of smoked sheet; but generally they are amalgamated with the rinsings of cups and buckets, treated with sodium bisulphite and acid, and made into crepe form. The cup-washings, as they arrive at the store, represent a very dilute latex, the rubber from which is generally of a greyish colour.