274 



POPULAR SCIENCE MONTHLY. 



discussion of current problems, at- 

 tempts, assisted by the lessons of the 

 past, to indicate the probable future 

 movement of thought, springing out of 

 present economic conditions. 



Mr. Wilbur S. Jackman has sought in 

 preparing his manual of Nature Study 

 for Grammar Grades* to propose a few 

 of such problems arising in a thought- 

 ful study of Nature as are within the 

 comprehension of grammar-school pu- 

 pils, and to offer suggestions designed 

 to lead to their solution. Directions 

 may perhaps be given by the teacher 

 that is, by some teachers, but very few 

 but even if he knows how, it is hardly 

 possible for him to make them as sys- 

 tematic to so large an extent as would 

 be required by a school of inquiring 

 pupils; and such a plan as the author 

 offers may be accepted as a valuable 

 help. Take, for instance, the first les- 

 son on the mutual relations of plants 

 and insects as to plants. The student 

 is told what equipment to take, what 

 places to visit; is reminded of seven 

 kinds of evidence in the shape of galls, 

 stings, eaten leaves, etc., to be consid- 

 ered; and is given a list of queries to be 

 recollected in studying the phenomena, 

 in their general aspect, as to the benefit 

 or injury received by the plant from 

 insects, the attractions it offers, and 

 the defenses it possesses, with " number 

 work " relating to the extent of the 

 depredations, and methods of represent- 

 ing the results of the study in picture. 

 The book contains forty-five such les- 

 sons on different aspects of Nature. 



In the preparation of his book on 

 Fertilisers f it has been the aim of Mr. 

 Voorhees to point out the underlying 

 principles and to discuss, in the light of 

 our present knowledge of the subject, 

 some of the important problems con- 

 nected with the use of fertilizing mate- 

 rials. While the author recognizes the 



* Nature Study for Grammar Grades. A Man- 

 ual for the Guidance of Pupils below the High 

 School in the Study of Nature. By Wilbur S. 

 Jackman. Danville, 111.: The Illinois Printing 

 Company. Pp. 407. 



t Fertilizers. The Source, Character, and 

 Composition of Natural, Home-made, and Manu- 

 factured Fertilizers; and Suggestions as to their 

 Use for Different Crops and Conditions. By Ed- 

 ward B. Voorhees. New York: The Macmillan 

 Company. Pp. 336. Price, $1. 



lack of definite knowledge on many 

 vital points, he considers it desirable, 

 when the investigations of the experi- 

 ment stations are becoming so impor- 

 tant and they are so well prepared to 

 study the fundamental principles of 

 plant nutrition, for the practical man to 

 have a clear understanding of what is 

 now known. The book treats of the 

 natural fertility of the soil and the 

 sources of the loss of the elements of 

 fertility, the functions of manure and 

 fertilizers and the need of artificial ones, 

 the different classes of fertilizers, the 

 chemical analysis of them, and the 

 methods of using them with their spe- 

 cial application to various crops. 



We have received, with only a short 

 interval between them, the first volume 

 of a third edition and the fourth or 

 last volume of the second edition of 

 Alfred H. Allen's Commercial Organic 

 Analysis.* The former volume is first 

 to reach us. It is a high testimony to 

 the value of the work in itself that the 

 publication of a rival issue of the edi- 

 tion of 1885 had been begun by another 

 house, although its age, as suggested by 

 the date, would indicate that it had 

 much need of revision. During the thir- 

 teen years since the publication of this 

 edition later research has thrown new 

 light on many features of the science 

 and processes, and has corrected many 

 of the old conceptions, and the author's 

 views on some points have changed in 

 the light of the more recent results, so 

 that the preparation of a new edition 

 had become necessary. Mr. Allen has 

 found it now impossible for him to un- 

 dertake the continuous labor which 

 would be imposed by such a task, and 

 the work of revision has been under- 

 taken by Henry Leffmann, of Philadel- 

 phia. For this new edition Mr. Allen 



* Commercial Organic Analysis. A Treatise 

 on the Properties, Proximate Analytical Examina- 

 tion, and Mode of Assaying the Various Organic 

 Chemicals and Products employed in the Arts, 

 Manufactures, and Medicine. By Alfred H. Allen. 

 Third edition. Illustrated. With Revisions and 

 Appendix by the author and Henry Leffmann. 

 Vol. I. Introduction. Alcohols, Neutral Alco- 

 holic Derivatives, Sugars, Starch and its Isomers, 

 Vegetable Acids, etc. Philadelphia : P. Blakis- 

 ton, Sons & Co. Pp. 557. Price, $4.50. 



The same work. Second edition. Revised and 

 enlarged. Proteids and Albuminous Principles, 

 Proteids or Albuminoids. Same publishers. 

 Pp. 584. Price, $4.50. 



