"500 Plain Answers on Steam, Hot Water Vapor & Vacuum Heating" by Alfred G. King is a book published in 1928 by Norman W. Henley. It is a comprehensive resource that provides clear and concise answers to various questions related to steam, hot water vapor, and vacuum heating. Written in English, this book is a valuable tool for those looking to enhance their understanding of these heating systems and their applications. With detailed explanations and insights, readers can expect to gain a deeper appreciation for the principles and technologies surrounding these heating methods.