PKRIODICAL LITKRATURK 353 



twigs, as in hedge trimming, tends to increase the yield of camphor in 

 the next growth. (4) Any commercial plan of harvesting should pro- 

 vide a material high in yield, with a minimum amount of low-yielding 

 wood and with least injury to the trees. (5) Even slight shade tends 

 to decrease the percentage yield of camphor in the leaves and to reduce 

 the leaf area of the tree. (6) A considerable yearly variation may be 

 expected under varying climatic conditions and rainfall. (7) To a 

 considerable extent, the yield of camphor is proportional to the rate of 

 growth, and forcing the rate of growth of the trees will give a larger 

 tonnage of material yielding higher in percentage of gum. (8) Higher 

 percentages were secured on the better soils, especially those contain- 

 ing considerable amounts of clay. Under extreme stunted conditions 

 of growth the percentage of camphor in the leaves may be rather high. 



B. L. G. 



Factors Causing Variation in the Yield of Camphor in the Florida Camphor 

 Tree. Journal of Industrial and Engineering Chemistry, June i, 1917, pp. 552-555. 



The hardwood forests of Japan produce an ex- 

 The Hard and Soft cellent quality of oak, ash, birch, beech, and a few 

 Woods of other hardwoods. Oak constitutes the principal 



Japan export of lumber from Japan, though a little ash 



(tamo and sen) and birch are also exported. All 

 of the softwood produced in Japan is used locally. Larger sizes of 

 softwoods are imported from the United States. Large forests of 

 beech remain unexploited, though the rapid expansion of Japan's hard- 

 wood industry is anticipated, due to the increasing number of furniture, 

 veneer, barrel, and other wood-working factories that are coming into 

 Japan. Prices for hardwoods are from 10 per cent to 15 per cent lower 

 than prices prevailing on the Pacific coast of the United States for 

 similar material. 



H. L. G. 



Japan's Production of Hard and Soft Wood. Eastern CominiTcc, January, 

 1918, pp. 34-35- 



With the development of methods for the con- 

 Turpcntinc xcrsion of cymene into toluol and cumcnc. which 



from can in turn be converted into tri-nitro-toluol and 



Spruce l)cnzoic acid, the saving of the 1,500,000 to 2,000,- 



c«o gallons of "spruce turpc-ntitic" that is an- 

 nually wasted in the sulphite paper mills in the Ignited States and Can- 

 ada becomes a distinct possibility. While it has been known for some 



