Kinematics and machine design

BOOK REVIEWS. KINEMATICS AND MACHINE DESIGN, b y Louis J. Bradford and George L. Guillet. 357 pages, illustrations and tables, 14 X 20 cms. New York, J o h n Wiley & Sons, Inc., London, C h a p m a n & Hall, Limited, 1943. Price $3.00. One feature which often distinguishes a modern textbook is its direct and simple approach to the subject. Much of the unessentials such as mathematical proofs and excursions into border-line subjects have been eliminated in the interest of brevity, and the resulting course of study is much more " s t r e a m - l i n e d " and condensed. The book at hand illustrates this fact. I t is the abridgement and consolidation of two t e x t s - - K i n e m a t i c s of Machines, by G. L. Guillet and Machine Design, by L. J. Bradford and P. B. Eaton. The general procedure is first definition, then explanation, then application and problems. The book is divided into two parts, the first being devoted to kinematics. Here, under the heading of General Considerations, are given definitions and, when necessary, worked out examples thus acquainting the student a t the outset with the method of treatment. Following this in order are the topics: velocities in mechanisms, slider-crank mechanisms, rolling contact, cam mechanisms, and then a number of miscellaneous mechanisms are grouped. Theories are outlined in a practical way. P a r t II is the larger part of the text. I t treats on machine design, b u t before entering into the discussion proper on the process of the design of a machine, the more i m p o r t a n t of the terms frequently used are defined. Then beginning with the topics of friction, lubrication, and bearings the t r e a t m e n t is directed to function clutches and brakes, shafts and couplings, screws and screw fastenings, gears and gear trains, belts and chains, springs, flywheels, flatplates, cylinders, and weld construction. A t the end there are given fifteen drafting room problems and a n u m b e r of useful tables. There is a sul~ject index for reference purposes. The t r e a t m e n t is characterized by worked out examples throughout. A t the end of chapters are practical problems for exercise and the answers to many are given. The book is useful as a text for students, as a refresher for engineers and as a reference. R. H. OPPERMANN. ENZYME TECHNOLOGY, by Henry Tauber. 275 pages, photographs and illustrations, I4 X 22 cms. New York, J o h n Wiley & Sons, Inc., London, Chapman & Hall, Limited, I943, Price $3.5 ° . The production of various compounds with the aid of microSrganisms offers the most fascinating problems. Some of these problems have been solved to the point of putting the organisms to work on a factory scale. Ever since Pasteur utilized this method there has been a growth of knowledge along these lines and of recent years a great increase in products of fermentation. The outlook now is an unlimited field for catalytic micro6rganisms and practical enzymology. The role and use of enzymes in industry, their preparation and their use in medicine is the coverage of this book. Reflecting the present position of the industry, the book starts out with a discussion on the relation to yeast production and utilization, the production of ethyl alcohol and the role of enzymes in brewing. Mold fermentations and bacterial fermentations, followed by the production of enzymes and methods for their estimation, are next taken up. Enzymes for medical use is a heading under which a review is made not only of the use b u t of experimental progress. Special a t t e n t i o n is given to enzymes of grains and malt, and the role of enzymes in bread baking, in dairy products, and in the meat, egg, vegetable and fruit industries. The part t h a t enzymes play in other industries is also given space, including such 498