1002 



SCIENCE. 



[N. S. Vol. XIV. No. 365. 



line of study in a field where comparatively- 

 little beyond the result is known at present. 

 The book is written in a clear and entertaining 

 style that should commend it to the general 

 reader as well as the student. It is an impor- 

 tant addition to our agricultural literature, and 

 will be welcomed by many who have felt the 

 need of a general treatise on the subject. 



E. W. Allen. 

 The Feeding of Animals. By Whitman H. 



Jordan. New York, The Macmillan Co. 



1901. Pp. 450. 



This book by the director of the New York 

 State Experiment Station, is the latest contribu- 

 tion to the excellent Rural Science Series. Sev- 

 eral books on feeding have been published by 

 American writers, but in some ways this is the 

 most systematic and comprehensive treatment 

 of the subject, especially as adapted to the 

 needs of the student. While the teachings of 

 European experiments and experience are taken 

 account of, American conditions are kept con- 

 stantly in mind, and this gives the book a dis- 

 tinct advantage over some which have adhered 

 too closely to the German feeding methods. 

 Dr. Jordan has combined a quite thorough re- 

 view of the important scientific teachings on 

 the subject, with a plain and clear statement of 

 the application of these facts in practical feed- 

 ing. He has digested the investigation relating 

 to feeding at home and abroad, and gives the 

 reader the benefit of his judgment and insight 

 into the subject in interpreting and applying 

 them. The applications which he makes of the 

 science of feeding to practical conditions show 

 that he is not bound down by any theoretical 

 ideas or teachings but is thoroughly familiar 

 with the standpoint of the practical feeder. He 

 breaks away, in a measure, from the mathe- 

 matical doses of nutrients prescribed in feeding 

 standards, but at the same time he admits the 

 value of these formulas as an aid in selecting 

 adequate, uniform and well-proportioned ra- 

 tions. The first part of the book is taken up 

 with the principles of feeding, the relations of 

 plant and animal life, the composition and di- 

 gestibility of feeding stufis, the function of 

 nutrients and the laws of nutrition ; while the 

 second part considers the practice of feeding, 

 the selection and compounding of rations for 



maintenance, for milk and meat production, for 

 growing animals and for work, as well as ques- 

 tions of general management. The arrange- 

 ment of the book is logical and orderly, and it 

 is well suited to the needs of the student and 

 the class room ; in fact it may quite possibly 

 prove more popular as a text-book than as a 

 manual for the farmer or practical feeder, and 

 for such a text-book there is perhaps the greater 

 need at present. 



E. W. Allen. 



A Text-book of the Physics of Agriculture. By F. 

 H. King. Second edition. Madison, Wis., 

 Author. 1901. Pp. xvi + 604. Figs. 276. 

 In this book, which is by the professor of 

 agricultural physics in the University of Wis- 

 consin and physicist of the experiment station, 

 " the aim has been to present to the student 

 who expects to be a farmer some of the funda- 

 mental principles he must understand to become 

 successful." The author states that it is his 

 purpose to present these principles from the 

 physical rather than from the chemical or bio- 

 logical standpoint, and from that of the general 

 student and farmer rather than from that of 

 more technical scientific agriculture. Never- 

 theless, the book will be found to be a notable 

 contribution to the literature of scientific agri- 

 culture in a field which has not heretofore 

 received the attention its importance demands. 

 The introduction deals briefiy with certain gen- 

 eral physical principles, laws and factors, a 

 knowledge of which is necessary to an under- 

 standing of their subsequent practical appli- 

 cation. Other chapters deal with the nature, 

 origin and waste of soils ; chemical and iliineral 

 nature of soils ; soluble salts in soils ; physical 

 nature of soils ; soil moisture ; physics of plant 

 breathing and root action ; movements of soil 

 moisture ; conservation of soil moisture ; rela- 

 tion of air to soils ; soil temperature ; objects, 

 methods and implements of tillage (especially 

 the plow) ; ground-water, farm wells, and 

 drainage ; principles of rural architecture, 

 including strength of materials (posts, barn 

 frames etc.), warmth, light and ventilation, 

 principles of construction, construction of silos; 

 farm mechanics, including principles of draft, 

 construction and maintenance of country roads, 

 farm motors (animal power, steam and gasoline 



