REVIEWS 1033 



gain over standard methods of $450 per crop per season. Narrow chip- 

 ping once a week reduced the yield of turpentine and rosin 17.5 per 

 cent, as compared with standard chipping. As the timber available for 

 turpentine orcharding is decreasing very rapidly, more intensive meth- 

 ods of orcharding are becoming imperative. According to the authors, 

 the main problem in applying the double chipping system is to find a 

 sufficient number of chippers, due to prevailing labor conditions. 



B. L. G. 



The Mineral Industries of the United States — Fertilisers: An Inter- 

 pretation of the Situation in the United States. By J. E. Pogue. Bul- 

 letin 102, Part 2, United States National ^Museum. Washington. D. C. 

 1917. Pp. 22. 



This is an excellent brief discussion of the needs of the fertilizer 

 situation, present and future, in simple language, explaining the func- 

 tions and actions of the most important fertilizers and the sources of 

 supply, the object being to stimulate government activity in regulating 

 their use. 



It appears that while potash could be and has been secured from 

 wood ashes, this source of supply is too insignificant. 



The Development of Forest Lazv in America. By J. P. Kinney. 

 John Wiley & Sons. New York. 1917. Pp. 254; xxi. 



This is a sequel to the author's volume, lately published, on The Es- 

 sentials of American Timber Laze, which we reviewed on page 254 of 

 this volume of the Journal, and it may be termed a by-product of the 

 work on the former volume, being the historical development of the 

 forestry movement in the United States as expressed in legal enact- 

 ments. 



While the author is naturally dealing only or mainly with facts, he 

 knows how to present them interestingly in their relationship. 



The construction of the book is based on a time and subject division 

 in seven chapters ; the time division refers to legislation had before 1900 

 and that of the twentieth century to date; the subject-matter refers to 

 forest administration laws, forest-fire control, encouragement of pri- 

 vate and municipal forests, Federal forest protection and administra- 

 tion ; and one chapter summarizes the progress in forest legislation on 

 brief twenty pages. 



This last. Chapter VI, is naturally of most interest to the casual 

 reader. It is divided into eight divisions, each with three to eight para- 



