181 



without materially checking the growth of the tree. The largest pro- 

 portion of camphor is contained in the older, larger roots ; the trunk, 

 limbs, twigs, and leaves containing successively a decreasing proportion. 

 When the camphor tree is killed nearly to the ground by frost it sends up 

 vigorous shoots from the base. It may be expected to do the same when 

 cut, especially if cut lat<> in the fall. Experiments are needed to deter- 

 mine whether this growth may be depended upon, or whether it will be 

 more profitable to dig out the larger roots and set out new seedlings. 



" Distillation. 



"In the native forests in Formosa, Fukien, and Japan, camphor is 

 distilled almost exclusively from the wood of the trunks, roots, and 

 larger branches. The work is performed by hand labour, and the 

 methods employed seem rather crude. Different methods of distillation 

 are employed in different districts, but those in use in the province of 

 Tosa, in Japan, appear to be the most skilful. The camphor trees are 

 felled, and the trunk, larger limbs, and sometimes the roots, are cut into 

 chips by hand labour with a sharp concave adze. 



" The fresh chips are placed in a wooden tub about 40 inches high 

 and 20 inches in diameter at the base, tapering toward the top like an 

 old-fashioned churn. The perforated bottom of the tub fits tightly over 

 an iron pan of water on a furnace of masonry. The tub has a tight- 

 fitting cover, which may be removed to put in the chips. Ic is sur- 

 rounded by a layer of earth about six inches thick to aid in retaining a 

 uniform temperature. A bamboo tube extends from near the top of the 

 tub into the condenser. This consists of two wooden tubs of difler- 

 ent sizes, the larger one right side up, kept about two-thirds full of 

 water from a continuous stream which runs out of a whole on one side. 

 The smaller one is inverted with its edges below the water, forming an 

 air-tight chamber. This air chamber is kept cool by the water falling 

 on the top and running down over the sides. The upper part of the air 

 chamber is sometimes filled with clean rice straw, on which the camphor 

 crystallizes, while the oil drips down and collects on the surface of the 

 water. In some cases the camphor and oil are allowed to collect together 

 on the surface of the water and are afterward separated by filtration 

 through rice straw or by pressure. 



" About twelve hours are required for distilling a tubful by this 

 method. Then the chips are removed and dried for use in the furnace, 

 and a new charge is put in. At the same time the camphor and oil are 

 removed from the condenser. By this method 20 to 40 pounds of chips 

 are required for 1 pound of crude camphor. 



" The principles generally held to be essential in distilling camphor 

 of good quality are : — (1) The heat must be uniform and not too great, 

 producing a steady supply of steam ; (2) the steam after liberating the 

 camphor must not come in contact with metal, that is, the tub and con- 

 densing apparatus must be of wood. 



" Suggested Improvements. 



" Many improvements upon the methods described can doubtless be 

 made, tending both to a reduction in cost and an increase in the pro- 

 portion of crude material obtained. Instead of an adze wielded by 



