OTHER TYPES OF SMOKE-HOUSE.--So far we have confined the arguments to smoke-houses of the usual type. There are others which vary in either design and method of working, or in the material of the structure. Mention may be made of the most prominent of these. BRICK HOUSES.--Some houses are constructed of brick, and may have one or two storeys above the furnace chamber. The floors are sometimes made of ferro-concrete, and the furnaces may also be of this material. These brick houses give satisfaction, but there would seem to be some difficulty in obtaining and maintaining the desired temperature, although it is not quite plain why this should be so. The principle of these buildings is the same as that of the ordinary iron house, and the suggestions made in previous paragraphs apply with equal force. "THIRD MILE" TYPE.--Reference has been made to the "Third Mile" type of furnace. This is an integral part of a smoke-house, which for clearness of distinction may be known as the "Third Mile" type of smoke-house, the original of which was erected on the Third Mile Estate, Seremban, F.M.S. [Illustration: "THIRD MILE" TYPE OF SMOKE-HOUSE.] In essence the design consists of a building, having two storeys for rubber-drying, and a shallow inverted pyramidal base, ending on the ground in "Third Mile" furnace, already described and illustrated. It will be seen that the principles of ventilation employed are those indicated for an ordinary house--viz., air-inlet near the ground (with little draught), and smoke-vent at the roof-ridge. The windows shown in the drawing are only for purposes of inspection of the rubber during the day, and form no part of the scheme of ventilation during the hours of smoking. It is claimed that the efficiency of the house is high. Certainly the work of attending to the furnaces is simplified, and there should be small ground for excuse if negligence is displayed. JACKSON HOUSE.--This was brought into notice under the description of the "Jackson Cabinet," and it was claimed that average sheets could be dried in a few days. It consisted of a small house of one storey, having several tiers of racks. Smoke and heat were generated in a small stove placed outside the wall. A smoke vent was provided in the roof. These cabinets had a certain vogue as part of a small unit installation, with a fair degree of success. It is not clear, however, that such speed in drying is required. (This point will receive further attention in a subsequent chapter.) "DEVON" TYPE.--In its full original design this type owes its origin to Mr. H. E. Nixon, General Manager of the Devon Estates, Malacca, where it forms part of unit divisional installations worked under a scheme of decentralisation. The original units consisted of a building erected with an iron framework covered with sheets of asbestos-slate, and a roof of galvanised iron.