THE FOKESTEE. 187 



became the meeting place of engineers and lumbermen's associations. 

 At the request of the Canadian and Tasmanian Governments, experts 

 from the staff were f urloughed to assist in drafting a policy for utiliz- 

 ing the forest resources of British Columbia and to study the pulp 

 and paper possibilities of Tasmania. Investigations of the paper 

 possibilities of several Chilean woods were made and similar tests 

 for the Argentine Government arranged. 



Close relationship was maintained with the various wood-using 

 industries, to the end that their problems may be clearly recognized, 

 and with individuals, companies, trade and other associations, and 

 technical societies interested in the use of wood and wood products, 

 that cooperation may be secured for demonstrating laboratory results 

 on a commercial scale. Service tests on the relative durability of 

 treated and untreated timbers were conducted in cooperation with 

 65 railroads, mining companies, municipalities, agricultural colleges, 

 etc. Cooperation on preservative paints and fireproofing compounds 

 involved 36 companies. Demonstration on a commercial scale of 

 laboratory results involved 11 cooperators. 



The strength tests of timber which have been continued for sev- 

 eral years have shown conclusively the need for grading rules for 

 structural timbers which will give an indication of strength. A 

 method of judging the strength of southern pines from the propor- 

 tion of summer wood in annual rings was developed, and this factor, 

 in combination with defects limiting strength, was used in formula- 

 ting grading rules which have been adopted by the American Society 

 for Testing Materials, the Southern Pine Association, and the Na- 

 tional Board of Fire Underwriters. Efforts are now being made to 

 work out similar rules for Douglas fir, and, in cooperation with 

 various agencies, to devise methods for testing boxes and similar 

 packages. 



The investigations of derived products were mainly the search for 

 improved methods of manufacture to increase yields. Temperature 

 control in hardwood distillation on a commerciad scale increased 

 the value of yields $335 per month in a 50-cord-per-day plant and 

 the methods developed are now being followed. An increase of 20 

 minutes in the time of digestion of sawdust increased the yield of 

 ethyl alcohol by 23 per cent, and the present status of investigations 

 indicates that western larch may be valuable as a source of alcohol. 

 Improved methods of turpentining demonstrated by laboratory ex- 

 perts have been adopted by one of the largest operators in the South. 

 Chemical analysis of the total cellulose contents of woods shows the 

 possibility of increasing pulp yields by improved methods from 5 to 

 20 per cent. Laboratory methods have shown the value of Osage 

 orange as a dyewood and substitute for materials not now available 

 for import sufficiently to justify its trial on a commercial scale. 



The work in wood preservation covered three principal lines: 

 Attempts to improve methods of preservative treatment, to prevent 

 or reduce losses from sap stain, and to improve methods of fire- 

 proofing. In cooperation with the Bureau of Fisheries considerable 

 progress was made in the determination of what substances are 

 most effective in preserving piling from attacks of teredo and other 

 marine borers. It was found that creosote can be used in silos with- 

 out contaminating the silage. Methods were developed for treating 

 wood blocks which will largely or altogether prevent swelling and 



