Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A History of Aircraft Piston Engines

A great deal of research went into this book and the net result is one of decent assemblage. As an alumnus of Parks College of Aeronautical Technology and as a Docent at Evergreen Aviation Museum in McMinnville, Oregon, I use this book frequently. In all my efforts, accuracy is of the utmost importance. This book satisfies me in my efforts. I only have one gripe with it, and it is relatively minor. There is a clear, well-defined, difference between engines and motors. Engines require heat energy in order to perform work and motors do not. Motors produce heat as a result of performing work...a big difference. It appears that the author is not aware of this and he continues to equate the terms (engines and motors). Other than that, he has done a fine job. I know the difference and, when asked or conducting a tour, I so inform visitors of this difference with a touch of humor. Regardless, I love the book. The author did a good job.