236 forestry Quarterly. 



This book carries the subheading "A manual of practical for- 

 estry for the use of foresters, students and laymen in forestry, 

 lumbermen, farmers and other land owners, and all who con- 

 template growing trees for economic purposes." 



With this object in view the book is divided into two parts. 

 Part I, occupying about one-third of the volume, is a simply 

 written compendium of information on artificial regeneration 

 practice and treatment of misused forests. Part II, forming the 

 bulk of the book, deals with the important American trees. 

 These are taken up consecutively, each being fully described, 

 together with the qualities and uses of the wood and the biologi- 

 cal characteristics of the species. 



The book is plainly written, free from technical discussion 

 with no attempt to introduce the theory of scientific forestry. It 

 is essentially a handbook for the layman who wishes to help 

 himself. J. H. W. 



Kiln Drying Douglas Fir and Other Northwestern Woods- . By 

 H. B. Oakleaf. Reprint from the Pacific Lumber Trade Jour- 

 nal, Seattle, Wash., March 15, 1913. Pp. 13. 



This study was undertaken by the U. S. Forest Service to 

 procure information on processes and apparatus used in kiln 

 drying Douglas fir, western hemlock, Sitka spruce, western red 

 cedar, and western yellow pine. A detailed study was made of 

 the methods employed at the various kilns in order that the 

 results obtained at the various kilns could be compared and 

 analyzed. The conclusions drawn from the results of the project 

 are as follows : 



1. Kilns operated with no draught from outside air and little 

 or no ventilation produce lumber which is more uniformly free 

 from checking and warping. 



2. Kilns using temperatures between 200 and 230 degrees F, 

 are producing excellent lumber with no appreciable discoloration 

 or brittleness, except where the boards are allowed to get too 

 dry. Higher temperatures (up to 300 degrees F.) produce sur- 

 face discoloration which does not seem to be harmful, for it dis- 

 appears in machining and the lumber is not noticeably brittle. 



3. The degree of heat and the method of piling to enable the 



