The second essential, but of equal importance, is that there shall be an ample open space on which the sun may shine all day. There must be no trees too near the buildings, and there should be no adjacent swamps. Preferably, the site should be on a raised position, so that it will be impossible for surrounding trees to cut off sunshine, even when they are fully grown. From such an arrangement it will follow that the factory will be light and airy, and the drying-houses will receive the maximum of benefit to drying from direct sunshine on the roof and walls. There can be little doubt that these considerations play a most important part in determining the rate of drying of the rubber, and where comparisons are made between the rates of drying in various drying-houses all these factors enter into the question and contribute to the total result. Presuming that the thin crepes made in two factories are equal in thickness, it is not uncommon to find that in a drying-house, situated in a wide open space, the period of drying may be as low as six or seven days; while in another drying-house, situated near a swamp and surrounded by trees, the period may be as high as eighteen days to twenty-one days. The figures quoted are not fictitious, but are facts actually noted in the course of the writers' experience. A great deal also depends upon the exact position of buildings. Thus, to obtain the maximum of light in a factory, it will be obviously beneficial to erect it with the long sides running east and west, so that the windows face the north and south, and the large end doors face the east and west respectively. At first sight it would appear that the best position for the machines would be on the north side of the building where no sun can enter; but a moment's consideration shows that the south side would give the best results. By the time the sun has come round to the south, it is usually high in the heavens, and the direct sunshine does not fall very far into the room. Even should it play upon the machines for an hour or two during the day, no harm could result to the rubber which was being worked, as no piece would remain there a sufficiently long time to be injured in the slightest degree. Placed in this position, the maximum benefit of light would be obtained, whereas if the length of the building ran east and west, the machines would have only either the morning or afternoon light. [Illustration: SUGGESTED ARRANGEMENT OF BUILDING.]