242 ANNUAL EEPOKTS OF DEPARTMENT OF AGRICULTURE. 



kiln-drying methods, and a broad study of air-seasoning methods was 

 initiated. 



Microscopic studies indicated that "brashness," at least in spruce 

 and ash, is due to incipient decay rather than to any structural 

 characteristics, and this, if established, may lead to practical methods 

 for its determination and elimination. Improved and cheaper 

 methods of preservative treatment, particularly of Rocky Mountain 

 Douglas fir ties treated with zinc chloride, were sought with success. 

 Studies designed to prolong the life of the naval stores industry in 

 the South through improved methods of turpentining were con- 

 tinued. 



Substantial improvement in the chemical products and by-products 

 of wood cellulose are dependent upon a much more exhaustive 

 knowledge of its chemistry than now exists. Research during the 

 year established significant facts which have a direct bearing upon 

 the most effective selection of material for chemical by-products. 

 The possible increase in yields under chemical pulp processes from 

 the 40 to 45 per cent now obtained to the theoretically possible yield 

 of 60 per cent without decided loss in the quality of the pulp depends 

 upon a much more exhaustive knowledge of cellulose chemistry. 



Investigations to improve the sidphite process developed a method 

 of analyzing cooking liquor which permits an accurate control of the 

 cooking time and pressure and thereby makes possible the accurate 

 regulation of the cook arid the quality of pulp desired. This method 

 is now being tested commercially and should permit a marked im- 

 provement in the cooking of sulphite pulp. It has also shown the 

 desirability of using water-saturated chips in the sulphite process — 

 a radical change from the present commercial practice of using air- 

 dried or even kiln-dried chips. Other important progress in pulp and 

 paper investigations includes the completion of comparative pulping 

 tests on approximately 100 commercial American woods; the de- 

 velopment of methods for the successful grinding of jack pine for 

 container board, which if commercially applicable will have a wide 

 bearing on the value and future utilization of the enormous quantities 

 of Lake States jack pine; and further work on a method for deinking 

 of news and magazine stock, which has been partially and will be 

 completely tested on a commercial basis. 



Investigations in the production of sugar and ethyl alcohol from 

 mill waste and sawdust showed that the yield of convertible sugars 

 should be increased 25 per cent by stronger sulphuric acid, without 

 appreciable increase in expense. Chemical studies of the sugars and 

 cellulose also showed the production of mannose during the hydrolysis 

 of wood cellulose and. thereby established a marked chemical dif- 

 ference between cellulose from cotton and from wood, a fact heretofore 

 denied by many authorities. The development of cattle food from 

 hydrolyzed sawdust has progressed satisfactorily, final tests com- 

 pleted during the year with University of Wisconsin experts having 

 shown that this material can be fed dairy cattle with good results 

 to the extent of one-third of the normal concentrated food. Con- 

 tinued research for a higher yield of wood alcohol in the destructive 

 distillation of hardwoods disclosed that sodium carbonate is by far 

 ■ the most effective of over 30 catalyzers, and gives a largely increased 

 product. Efforts will be made during the coming year to determine 

 its commercial applicability. 



