INDUSTRIAL RESEARCH IN FOREST PRODUCTS 



405 



of laminated construction, and for those which are ex- 

 posed to the weather and to moisture, water-resistant 

 glues are necessary. Before the war there were no rec- 

 ognized standard specifications for glue. An excellent 

 beginning was made in investigations of glues and their 

 proper manipulation during the war, and the results of 

 the work with waterproof glues and plywood at the 

 Forest Products Laboratory saved the country over 

 $5,000,000 in the procurement of this material during the 

 emergency ; but the bulk of the field still remains to be 

 covered. 



"For many purposes, such as furniture, vehicles, coop- 

 erage, and airplane manufacture, it is necessary to bend 

 wood. Practically nothing is known as yet of the con- 

 ditions under which this can be done most effective'v 



the application of results to the remainder of American 

 species in commercial use, especially to such important 

 species as Douglas fir, western hemlock, and some of the 

 more refractory hardwoods. While the more important 

 field is in methods of artificial drying, there is room 

 also for a great improvement in methods used in the 

 natural seasoning of wood. 



"The life of the four to six billion feet of timber which 

 decays in service each year could be lengthened from two 

 to four times by preservative treatment. The work 

 already begun to determine the efficiency of various pre- 

 servatives under various conditions of exposure and 

 when used with different species should therefore be 

 hastened and completed. 



"Preservatives not only prolong the life of treated 



A GLUE SPREADER 



This machine is used at the Forest Products Laboratory in connection with investigations into glues, plywood and laminated construction. 

 The illustration shows a veneer core being coated in both sides with water-resistant casein glue. Several glues of this type have been 

 developed at the Laboratory. 



and without the excessive losses at present common in 

 commercial plants which waste high-grade, expensive 

 materials. 



"On problems connected with the drying of wood, 

 much progress has been made in the development of 

 general laws and in their application to a few of our more 

 common woods and a few additional woods which can 

 not be seasoned easily. The work done has made it 

 possible, for example, to kiln-dry wood with safety for 

 airplane construction during the war. Much remains 

 to be done in the determination of general laws and in 



woods, but make it possible to utilize the less durable 

 species in the place of the more durable ones. Untreated 

 piling of the best species when placed in exposed con- 

 ditions is sometimes wholly destroyed in a few months. 

 Work so far done indicates for this specific use the possi- 

 bility of increasing the life to several years. Far too 

 little has been done in the development of fire-retarding 

 compounds for the impregnation of wood, and the possi- 

 bilities are practically unlimited. Enough has been done 

 in the study of methods of construction to show great 

 possibilities in the reduction of fire risks by the develop- 



