However, they also have importance since they may provide a window to the better understanding of how growth is controlled. The publication of this seminar is to be welcomed. It provides a useful review of much of the work in Europe and the USA. The review papers describe the structures and possible mechanisms of action of the/~-agonists, something of their pharmacology, their effect in growth and metabolism trials, side-effects where these have been observed, market requirements for lean meat and the safety criteria which will have to be met if they are to be acceptable. Work is described on cattle, sheep, pigs and poultry as well as reference to some of the laboratory trials with rats. This book provides a comprehensive and readable introduction to the subject for the research worker, teacher, advisor and consultant, as well as a very extensive bibliography. It also provides suitable material for the curious, and should have its place on the shelf of any library devoted to animal husbandry as well as on that of the specialist. D. Hovell
Rural Waste Management. By A. C. Varshney, Associated Publishing Company, New Delhi. 215 pp. Price: US$35. This book has been written with the objective of compiling the available information, probably for the first time, on generation, storage, collection, transfer and transport, processing and recovery and disposal of rural waste with particular reference to the Indian situation. It also contains results of work done by the author on related topics. Simple and low-capital intensive methods have been suggested for better management of rural waste. The book will, however, be useful to all the persons associated with management of rural waste in under-developed and developing countries. The typeface is clear, and black-and-white illustrations are understandable. SI units have been used, in general, except for energy, which has been expressed in calories. There are a few small errors, such as 'gram' being expressed both as 'g' and 'gm'. The book is divided into eight chapters. Each chapter, except the Introduction, contains a list of references at the end which number between 5 and 36. However, references have not been cited in the text except for tables and figures. A subject index has also not been given at the end of the book. The first chapter introduces the readers to the various types of wastes available from production and domestic activities in rural areas. It also includes explanations of various technical terms. The second chapter, in
general, gives the economic value of rural waste in terms of energy, manure and raw materials for industrial use. It also gives qualities of different types of rural wastes available in India. The third chapter gives information on the general composition and physical and chemical parameters of various waste materials. It also contains data on the detailed composition of a few selected wastes. Chapter 4 contains information on industrial uses of plant wastes for the pulp and paper industry, building materials and as fuel. It also contains essential information on the techniques and equipment for briquetting biomass (direct as well as pyrolysed) and basic information on gasification, liquefaction, hydrolysis and anaerobic fermentation of plant wastes. Very useful information on factors affecting composting are also given: various methods ofcomposting--their merits and demerits--characteristics of ideal compost and utilization of the compost. A note has also been included on methods of composting for villages and small towns and selection of the appropriate method of composting. Chapter 5 includes information on utility of animal wastes as animal feed, manure and, in a limited way, for industrial uses. It also includes useful information on biogas production and utilization, method of design of biogas plants and gas holders, and details of construction, operation and the merits and demerits of various designs and models of biogas plants. Chapter 6 contains information on various methods of processing of carcass and slaughterhouse wastes, such as hides and skins, fats, bones, horns and hooves, guts, glands, hair and blood from animals. Chapter 7 deals with various aspects of domestic waste. It gives details of various devices and methods for the collection, storage, treatment, salvage and disposal of wastes from houses, communal sites, streets, etc. Design details of the various improved sanitary latrines, latrine-cum-biogas plants, septic tanks and soak pits are given, keeping in view the unhygienic disposal of human faeces in villages. The last chapter on rural industrial waste gives, in brief, information on the use of by-products from ricemills, the cane-crushing industry, tanneries and semi-finished leather processing units. In conclusion, the author has made a very good start by compiling the available information on rural waste management. The book will be quite useful to professionals, extension workers, teachers and students in most of the under-developed and developing countries. The subsequent edition is expected to be much more refined and practically oriented.