SCIENCE— ADVERTISEMENTS 



New Editions 



Fundamentals of Bacteriology— Morrey "^Znon^ 



"THE FIRST EDITION won wide favor as a general text-book on the subject of bacteri- 

 » ology. The original method of presentation is preserved. The text-book idea is 

 adhered to, so that the individual instructor may have full liberty to expand on topics 

 in which he is especially interested. A number of illustrations have been added, the 

 text has been improved in many instances by the addition of further explanatory matter 

 and the most recent general advances in the Science. Examples are the System of 

 Classification of the Society of American Bacteriologists, which is used throughout the 

 text, their Key to the Genera of Bacteria, a discussion of the H-ion concentration method 

 of standarization, the selective action of anilin dyes, the mechanism of entrance Df 

 pathogenic organisms into the body, a more detailed explanation of the origin of anti- 

 bodies, the nature of antigens and a table of antigens and antibodies. 



A N experience of nearly twenty years in the teaching of Bacteriology has convinced 

 '^ the author that students of this subject need a comprehensive grasp of the entire 

 field and special training in fundamental technic before specializing in any particular 

 line of work. This text-book covers the first or introductory semester's work, and 

 requires two classroom periods per week. Each student is compelled to take two 

 laboratory periods of three hours per week along with the class work. The outline of 

 the laboratory work is given at the end of the text. Results attained seem to justify 

 this plan. 



P\R. MORREY has visited all the important laboratories in Germany, Austria, Russia, 

 '-^ Denmark, Holland, and also Paris and London, and is personally acquainted with 

 the foremost bacteriologists of these countries. This rich experience and wide acquaint- 

 ance guarantee the accuracy of his work. Also the author has made a thorough review 

 of the literature of Bacteriology, covering the standard text-book as well as works of 

 reference and the leading periodicals. Thus the latest information has been incor- 

 porated. The majority of the illustrations are original. 



By CHAR1.ES B. MORREY, B.A.. M.D., Professor ot Bacteriology and head of the Depart- 

 ment, Ohio State University. ISiuo, 330 pages, witli 171 engravings and 6 platen. 



Cloth, .¥3.25 net. 



Chemistry of Agriculture — Stoddart 



New {2d) 

 Edition 



IVAANY improvements and additions will be noticed in this new edition. Much new 

 '"^ material has been added and parts have been rewritten to make the subject clearer. 

 At the end of each chapter is a list of suggestive exercises. These make the reader think 

 and drive home to him the gist of the subject matter and its application to practical 

 conditions. Sections have been added on colloids, now a very important part of agri- 

 cultural chemistry; on new fertilizer materials, showing the development of our own 

 potash resources as a result of the Great War, and also of synthetic nitrogenous ferti- 

 lizers. To facilitate the teaching of the subject the order of the first three chapters has 

 been changed. The chapters on the Chemistry of Animal Physiology and Food and 

 Digestion have been changed and amplified. 



THE opening chapters deal with the conditions requisite to seed germination; with the 

 • chemical constituents ot plants and plant food; the availability and conversion of 

 food elements in the soil, and with the chemistry of plant products. Under crop 

 chemistry are shown the chemical constituents of the various crop plants and the drain 

 made by each on the supply of available plant food in the soil. The soil, its physical 

 and chemical composition, is treated in the light of the knowledge previously conveyed. 

 In logical sequence are taken up the correction of acid soil; the adaptability of soils to 

 cropping under various conditions, and the maintenance and restoration of soil fertility 

 by means of commercial fertilizers, nitrogenous crops and farm manures. 



THE applications of Chemistry in animal husbandry, in the dairy and in the destruction 

 1 of insect pests and parasitic growths, particularly in the preparation of spraying 

 compounds, are presented in such form as to be of definite practical value to the farmer. 



By CHARLES W. STODDART. Ph.D., Professor of ARricultura! Cliemistry. Pennsylvania 

 State College. 12mo. 340 pages, with 84 illustrations. Cloth, ¥2.50 net. 



Catalog gladly sent on request 



706-10 Sansom St. LEA & FEBIGER PWladelphia 



