NEED FOR INCREASED CARE WITH LOWER GRADE RUBBER.--In the ordinary procedure of estate-working there appears to be an undesirable variety in the style of lower grade crepes. On some estates an examination of these rubbers would appear to suggest that there need be no expenditure of care in the preparation or the form in which it is made. This is a great mistake. With the exception of the lowest grade (earth-rubber), it would not be unfair to state that the quality of the rubbers on testing should be very little inferior to the No. 1 product. Often, as in the case of naturally coagulated rubbers, they are superior in some respects to ordinary fine pale crepe. Doubtless manufacturers are aware of these facts, but what course is open to them if they find the rubber spoiled for their purpose by the presence of particles of sand, grit, or bark? The possible injury caused by these ingredients cannot be insisted upon too strongly, and it must be evident that great care should be exercised in the preparation of the lower grades of crepe. As to the particular form of the lower grade crepe rubber, one may apply the remarks made under the section dealing with the best grades. It is common to find thin crepes, medium crepes, and "blanket" crepes. More often than otherwise, the medium and thicker crepes are prepared direct in those forms. It follows that they are liable to attacks of "spot" disease, which, however, is not easily visible in the lowest grades, owing to the dark colour of the rubber. Furthermore, it is not possible to cleanse the rubber so thoroughly if thick crepes are made. BLOCK RUBBER.--Few estates now prepare block rubber, which is essentially crepe rubber pressed into blocks. In the ordinary process the fresh coagulum is lightly rolled into thin crepe, which is then vacuum-dried. There are slight variations in the subsequent procedure. Sometimes the rubber as it comes from the vacuum drier is merely allowed to remain on racks overnight before blocking. In other instances, the sticky rubber from the vacuum drier is passed once or twice through wet, smooth rolls and hung to dry for some days. The dry crepe is then folded into the pressing box or cut to suit the size of the box. Pressure is applied for some time, and finally the rubber is taken out in one homogeneous mass. Naturally the appearance of the block depends upon the quality of the parent crepe. Some block rubber is made up thick; other is made in slabs about 3 inches or 4 inches in thickness. With the latter, it should be possible, when held up to the light, to see the shape of a hand held between it and the source of light. It is possible that an erroneous idea of the strength of block rubber has been formed. It should only be necessary to point out that essentially block rubber is merely pressed crepe rubber. It is inconceivable that the mere action of pressing layers of crepe together would increase the physical quality of the rubber.