This book, Guide to Electrotherapy Instruments and History of Their American Makers, was written for educational purposes and to help collectors identify and date their medical electrical batteries. The contributions of major American manufacturers of electrical batteries for physician and home use are provided in this book that also describes and illustrates their products. Some selected tips in collecting, and waveforms of several batteries provide basic information not readily available to collectors in this field. A synopsis of electricity in medicine is provided along with information contained in rare trade catalogs. This book provides in a single volume information about medical electrical batteries that is scattered over difficult to locate and retrieve private and public sources. The years, 1852 to 1932, covered in the book represents the periods of time leading up to, and the declining years of the so called golden era of the medical electrical battery in the United States.