104 JOURNAL Ol? FORESTRY 



name for a type of raft used in certain parts of South America. The 

 wood is soft, spongy, and, as has been stated before, very light, its 

 specific gravity having been given as 0.120. It is used for hfebelts, as 

 cork substitute for bottle stoppers, and for fenders for lifeboats. Ex- 

 ])eriments to test its suitabilit)', in the form of wood meal, as a material 

 for increasing the sensitiveness of blasting explosives did not give satis- 

 faction ; others, however, indicate it to be valuable for an insulating 

 material and for woodpulp for paper-making. 



Experiments in the use of sawdust for pulp for newspaper have been 

 carried on in Great Britain with good success. Grinding mills convert 

 sawdust into wood-flour, fresh sawdust being better, as it can be ground 

 finer, than dry sawdust Most satisfactory results have been obtained 

 by mixing 35 per cent of sawdust pulp with 30 per cent of waste 

 (paper), or altogether 65 per cent of home material and 35 per cent of 

 imported pulp. Previously proportions were reversed, being about 70 

 per cent of imported pulp, with 30 or 40 per cent of home materials. 

 /\.n estimate places the amount of sawdust pulp to be obtained from the 

 United Kingdom per annum at about 20,000 tons. 



The Missoula, Montana, office of the Bureau of Aircraft Production 

 has a method of testing pine trees to ascertain whether they will yield 

 wing-beam stock. It consists in making a cut in the butt of the tree 

 and at this point taking a test chip, which must split straigJit both z^'ays. 

 No churned or tapered butts are acce])table, and all logs must have a 

 minimum taper. 



Precautions against overripe timber have been issued. Logs with 

 knot defects on one side, however, may be cut if clear airplane cuttings 

 can be obtained from one side. 



Pine for wing beams must have not less than six annual growth rings 

 per inch when measured in a radial direction through the zone of maxi- 

 mum growth on either end section. Wood showing not less than 18 

 annual growth rings in three inches is rejected. 



Specifications for pine logs require them to be cut 20 feet 6 inches in 

 length to yield stock 3 by 4^/2 — 19 feet 11 inches in length. 



Among the fossils found in North Dakota is what appears to have 

 been the immediate ancestor of the gingko, or maiden-hair, tree of 

 China and Japan. This strange tree has come down to us practically 

 unchanged from earliest Mesozoic time. During the Jurassic period it 



