FORESTRY AND FOREST MANAGEMENT 357 



annually. The waste material from many saw mills is now 

 distilled by various processes, producing great quantities of 

 wood alcohol, turpentine, formaldehyde, tar, creosote, and a 

 variety of other products. The gases given off in some of 

 these processes are used as fuel, and the charcoal which' 

 remains is valuable. A cord of long-leaved pine will produce 

 in this way twenty-four gallons of turpentine, thirty-three 

 gallons of pyroligneous acid, used in making vinegar, explo- 

 sives, and, when united with other substances, many pig- 

 ments ; one hundred and twenty gallons of tarry and oil 

 products, which may again be distilled ; and there remain 

 fifty-six bushels of very good charcoal. 



371. Other Wood Products. The making of veneers 

 (thin slices or sheets of wood) has become an important 

 industry in late years. Formerly only the expensive woods 

 were used in this way, and the veneers of these woods were 

 put over cheaper woods in the manufacture of furniture; 

 but now many of the cheaper woods are cut into veneers, 

 from which boards can be built up that are lighter and 

 stronger than if they were made of a single piece, and are less 

 likely to warp. Excelsior, made by shredding the wood with 

 sharp spurs or knives, is used in great quantities in making 

 mattresses, in upholstering, and in packing glassware, furni- 

 ture, and metals, as well as in a number of other ways. The 

 making of maple sugar and sirup is an important industry 

 in Vermont, New Hampshire, and New York ; and maple 

 sugar is made to some extent in all the north central states. 

 Most of this work is done between the middle of March and 

 the middle of April. A single tree may produce in a season 

 about two pounds of sugar or a quart of sirup. 



