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and very similar to that used by the Japanese in Formosa, with 

 slight improvements in the condensers, as perfect condensation is 

 absolutely essential for success. The slightest smell of escaping 

 camphor may mean a loss of 20 per cent, or more, as has been 

 proved by several experiments, and the two means of preventing 

 it and obtaining the maximum proportion of camphor to oil are 

 absolute condensation and sloiv distillation with a minimum of 

 heat. 



The still may consist of an ordinary wooden cask, but is better 

 if somewhat conical in shape, and should be about 6 feet high, 

 feet diameter at the bottom and 2 feet 6 inches at the top ; and 

 have a close fitting door at the lower end for the removal of the 

 refuse prunings. The top or a portion of it must be removable, 

 but capable of being hermetically closed. From near the top a 

 large diameter bamboo 5 to 7 feet long passes to the condensing 

 boxes of wood placed in a suitable tank and connected with short 

 lengths of similar bamboo. The still has a perforated bottom and 

 stands over an iron basin built into a small stone or brick furnace. 

 The basin about 2 feet 6 inches to 3 feet in diameter is filled with 

 a supply tube for adding water as required and an overflow pipe 

 closed with a plug during distillations. The condensing boxes 

 consist of bottomless boxes of suitable size, having 3 or more 

 partitions in each with communications at opposite ends of each 

 division to insure thorough circulation of the camphor and water 

 vapours. The tops of the boxes are hermetically closed about one 

 inch below the upper edges, and the boxes are stood in the tank 

 as mentioned above, being connected by short bamboo lengths. 

 Cold water from a stream flows from a pipe or bamboo on the top 

 of each box and then over-flows into the tank, which has an outlet 

 pipe 2 to 3 inches from the bottom. By this means a water seal 

 3 inches deep is kept round the bottom of the boxes. The mixture 

 of camphor, vapour and steam from the still enters the first box 

 just above the water level, circulates round the various partitions, 

 and so passes from box to box, the camphor being condensed in 

 pure white crystals on the walls and partitions as it cools down. 

 The last box is filled with an outlet of bamboo, which can be kept 

 closely plugged with straw. This acts as a safety valve, and 

 enables one to ascertain whether condensation is perfect, as there 

 should be little or no smell of camphor observable. In working, 

 the still is loosely filled with the fresh prunings as brought in, the 

 top put on and well luted with clay, water poured into the basin, 

 and a fire lit to bring it rapidly to the boil. \s soon as 

 this occurs and a slight smell of camphor or eucalyptus can be 

 smelt at the escape tube on the last box, the fire is reduced and 

 the water merely kept hot for several hours. A good plan is to 

 have a glass let into the cover of the first, (or all) of the condensing 

 boxes and as soon as vapour begins to condense on it, to im 

 mediately reduce the fire to a minimum, as the object to be gained 

 is to drive off all the camphor with as little steam as possible. A 

 small wooden spigot in the top of the still makes it possible to 

 ascertain when all smell of camphor has disappeared, but care 



