viii Contents. 



CHAPTER XVII. 



INSECT RAVAGES IN WOODLANDS. 



General Statements — Effect upon Wood-growth — Coleoptera — Orthop- 

 teia — Hemiptera — Neuroptera — Lepidoptera — Hymenoptera — Bip- 

 tera— Insects that attack the Oaks — Elms— Hickories— Black Wal- 

 nuts— Butternuts-Chestnut — Locust — Maples — Cottonwoods — Pop- 

 lars—Lindens — Birches — Beech — Willows — Pines— Spruces — Firs- 

 Hemlocks 161-187 



CHAPTER XVIII. 



PROCESSES FOR INCREASING THE DURABILITT OF TIMBER, OR FOR IMPROVING 



ITS QUALITY. 



General Statements — Causes of Decay — Charring — Immersion in Water 

 — Penetration of Liquids, and of Solids in Solution — Oils — Crude 

 Petroleum — Salt — Incombustible Wood — Alum — Borax — Lime — 

 Processes of Bethell — Boucherie — Burnett — Carey — Hatsfield — Ky an 

 Margary — Payne — Prescott — Robbins — Tait — Thilmany — Re- 

 cipes 187-199 



CHAPTER XIX. 



RESINOUS AND OTHER PRODUCTS OF CONIFERS. 



Naval stores — Turpentine — ^Spirits of Turpentine — Rosin — Methods of 

 Resinage — Economy and Waste — French Methods with the Maritime 

 Pine — Tar — Pitch — Lamp-black — Canada Balsam — Essential Oils — 

 Perfume from Pine-sap 199-205 



CHAPTER XX. 



USE OF WOOD IN THE MANUFACTURE OF PAPER. 



Mechanical Processes of Volter, Hartmann, Siebricht, etc. — Chemical 

 Processes — Cultivation of Poplars for Paper Pulp 205-206 



CHAPTER XXL 



TANNING MATERIALS. 



Supplies from the Oak — Hemlocks, etc. — Tanning Extracts — Manage- 

 ment of Oak-Coppices — Peeling by the Aid of Heat — Sumac. 206-210 



