Timber [antikvár]

PREFACE TO THE THIRD EDITIONIn preparing the third edition of my book, the difficulty has been to decide how much of the knowledge amassed by research organizations all over the world in the last five years should be incorporated in a work of this nature. It seemed most desirable to retain a simpUfied presentation of all important aspects of the subject within the compass of a single volume. I have, therefore, taken the opportunity to revise the text in several places, without greatly altering the original framework, adding only to those sections that interest a wider audience than when the book first appeared. I am particularly indebted to my Publishers for agreeing to the inclusion of several additional illustrations.The sections on the " Classification of trees " and " Nomenclature of timbers " have been rewritten in an attempt to clarify the difficulties laymen experience with timber names. To meet the needs of students preparing for trade examinations, two pages of text figures, and brief descriptions of microscopic features used in the identification of softwoods, have been added. The chapters in Part III have been rearranged, so that the occurrence of moisture in wood, which affects most other properties of timber, is now discussed before density and strength properties.The increasing incidence of fungal and insect activity has focussed attention on these pests of wood, and the development of several new proprietary preservatives, backed by intensive advertising campaigns, is tending to exaggerate the seriousness of the problem. The chapter on " Defects in timber " is now confined to natural defects in wood and seasoning degrade, fungi and insects being discussed in separate chapters, and a new chapter on " The eradication of fungal and insect attack" has been added after that on " The preservation of wood ". This analyses the alternative curative measures in an impartial manner, which it is hoped wiU counter commercial advertising of proprietary products : each case is different, and there is no universal remedy.It must be admitted that serious damage is caused by fungi