The camphor is found in the concrete state in which we see it, in natural fissures or crevices of the wood, but does not exhibit any exterior appearance by which its existence can be previously ascertained, and the persons whose employment it is to collect it usually cut down a number of trees, almost at random, before they find one that contains a sufficient quantity to repay their labour, although always assisted in their research by a professional conjurer, whose skill must be chiefly employed in concealing or accounting for his own mistakes. It is said that not a tenth part of the number felled is productive either of camphor or of camphor-oil (meniak kapur), although the latter is less rare; and that parties of men are sometimes engaged for two or three months together in the forests, with very precarious success. This scarcity tends to enhance the price. The tree when cut down is divided transversely into several blocks, and these again are split with wedges into small pieces, from the interstices of which the camphor, if any there be, is extracted. That which comes away readily in large flakes, almost transparent, is esteemed the prime sort or head; the smaller, clean pieces are considered as belly, and the minute particles, chiefly scraped from the wood, and often mixed with it, are called foot; according to the customary terms adopted in the assortment of drugs. The mode of separating it from these and other impurities is by steeping and washing it in water, and sometimes with the aid of soap. It is then passed through sieves or screens of different apertures in order to make the assortment, so far as that depends upon the size of the grains; but much of the selection is also made by hand, and particular care is taken to distinguish from the more genuine kinds that which is produced by an artificial concretion of the essential oil. CAMPHOR OIL. The inquiries I formerly made on the subject (not having been myself in the district where the tree grows) led me to believe with confidence that the oil and the dry crystallized resin were not procured from the same individual tree; but in this I was first undeceived by Mr. R. Maidman, who in June 1788 wrote to me from Tappanuli, where he was resident, to the following effect: