70 FORESTRY [Bot. Absts., Vol. IV, 



velopment along similar lines in Germany, through his Society for Applied Entomology and 

 his Zeitschrift fur Angewandte Entomologie, and has laid the beginnings of a Research In- 

 stitute in Munich, to study methods of combating insect pests injurious to farms, forests, 

 and farm and forest products and articles made from them, as well as to domestic animals 

 and human beings. The Institute is to be exclusively for research, not for instruction, but is 

 to publish its results in language that can be understood by practical farmers, foresters, and 

 manufacturers. — Escherich emphasized the necessity of a universal application of control 

 measures — no use to.control a pest on one area and not on the adjacent one — but prefers to 

 accomplish this through education of the public rather than forcibly through laws. This can 

 be done through teachers of winter short-courses, through traveling teachers, and through 

 technically and practically trained insect-pest inspectors who shall keep posted on the develop- 

 ment of the science and pass their knowledge on by means of demonstrations and otherwise. 

 There is perhaps not much hope of making the older generation receptive to such educational 

 propaganda, but much can be done with the coming generation, particularly if elementary 

 instruction regarding the principal beneficial and noxious insects can be given in the public 

 schools. — Dr. Seitner is pushing the development of a similar scheme in German Austria. He 

 suggests a central office, well furnished with equipment and trained personnel, and state ento- 

 mologists or traveling inspectors to collect information and statistics and carry on control 

 work. — W. N. Sparhawk. 



458. Pratt, M. B. The glory of the redwoods threatened by fire. Amer. Forestry 25: 

 1443-1445. 4 fig. 1919. — An account of the fires of the summer of 1919, which are said to have 

 been the largest in southern California since 1910. There occurred the first fire in Redwood 

 Park in modern history. One hundred redwoods were destroyed. The big redwoods do not 

 burn readily, but become weakened by brush fires about their bases and finally topple over 

 with a great crash, carrying smaller trees with them. Many of the redwoods had been hol- 

 lowed by previous fires four hundred or five hundred years ago, and so fell more readily before 

 the flames. — Chas. H. Otis. 



459. Record, S. J. Lignum-vitae, the vital wood. Sci. Amer. Supplem. 88:4-5, 15-16. 

 6 fig. 1919. — The propeller shaft of every large steamship revolves in wooden bearings. Lig- 

 num-vitae, of the genus Guaiacum, is the only wood suitable for such bearings, and this is 

 due to certain peculiar properties of the wood. The density of the wood enables it to with- 

 stand enormous loads; the interwoven fibers keep it from splitting and tearing apart under 

 impact; the infiltrated resin acts as a lubricant, preventing friction and eliminating the 

 danger of an overheated bearing, besides serving to protect the wood from the softening effect 

 of water. Besides this most important use of lignum-vitae for stern bearings, the wood is 

 used for bowling balls, rollers for furniture casters, mallets, sheaves of pulleys, railroad ties, 

 grate fuel and numerous small uses. The sawdust is in demand by the drug trade. Cuban 

 lignum-vitae logs are mostly 4 to 8 feet long, with diameters of 6 to 24 inches, and are of good 

 quality. The lignum-vitae from Jamaica, Bahama Islands and Porto Rico is small, usually 

 not exceeding 5 inches in diameter, and is of good quality. Santo Domingo, Haiti and Nica- 

 ragua supply considerable amounts of lignum-vitae. Mexico furnishes but a small amount 

 at the present time. The West Indies will probably continue to supply the bulk of the high- 

 grade lignum-vitae for many years if prices remain at sufficiently high levels to warrant the 

 increased expense attending the more and more difficult logging. Substitutes for lignum- 

 vitae have been suggested and tried for stern bearings and other exacting uses, but nothing 

 acceptable has been found. — Chas. H. Otis. 



460. Riley, S. Prevention of forest fire losses. Amer. Forestry 25: 1260-1263. 7 fig. 

 1919. 



461. Ronge, Eric W. Grafiska utbytestablaer. Enkel metod for upprattandet av en 

 praktiskt nojaktig utbytestabla. [A graphic method of constructing volume tables.] Skogen 

 6:-69-84. Fig. 1-15. 1919. It is established that each "form class" in trees has a corre- 

 sponding proportional "taper series" between breast-height and the top of the tree. Thus, 



