National Geographic : 1951 Jul
113 National Geographic Photographer B. Anthony Stewart A Kentucky Folk Song Virtuoso Touches Up His Homemade Dulcimers The oriental dulcimer was a forerunner of the piano (page 131). These instruments, made of native American woods, are its direct descendants. John Jacob Niles, who makes and plays dulcimers, uses spruce for the tops, curly maple for the sides, and walnut for the backs. After window glass cracked and flames licked through the wooden walls, a water spray put out the fire. The technicians were study ing combustion temperatures of structures, fittings, and furnishings made from wood. This was just one of hundreds of tests under way that day in the Forest Products Labora tory, finest of its kind in the world. Wood "Has Everything" What are the qualities of wood that make it such a favorite? Wood is made up of countless tiny tubes of cellulose, bound together and impregnated with lignin, trees' natural "glue." This fibrous structure gives great load-bearing strength, as in posts and piling. Parallel to the grain, wood's resiliency and tensile strength are phenomenal. Think of the beating a diving board takes! Wood fa tigues very slowly, and resists weather and decay like few other organic materials. Most wood shows amazing resistance to shock. Like a good boxer, it "rolls with the punches"-essential where exposed to repeated impact, as in shuttle blocks and bowling pins. Wood appeals to human senses; its rich ap pearance and pleasing hue attract the eye. That's not all! Unlike cold-feeling metal, glass, and stone, wood is neutral to the touch, a poor conductor. Many species have pleasant perfumes. Wood is compact and clean, it floats (most species), and is easy to work. It takes stains, paints, and other finishes smoothly. Several dense woods sink like rocks in water. By contrast, feather-light balsa floats like a cork, yet is strong enough to use in full-scale and model airplanes. Balsa allows clowns to lift "impossible" weights and collapsing "tim bers" to leave actors' heads undented. Two of the best things of all about wood are: it is still generally abundant; and it's a renewable resource. Some useful kind of tree will grow on almost any kind of land, save in regions of climatic extremes. United States Is a Wood Workshop "From sea to shining sea" the forest-blessed United States is a giant wood workshop. Our forefathers found a wealth of oak and maple, birch and ash, white pine and spruce in New England, New York, the north-central States, and the southern Appalachians. They built mills that were the nucleus of today's furniture, implement, and flooring industries.