"This good-looking volume would grace any aviation enthusiast's coffee table. It's printed throughout in colour on high grade paper and, in addition, there's an Al size copy of a detailed drawing of an ARl, plus a CD containing seven appendices in PDP format. These contain good scans of various company and Air Ministry booklets, including instruction books, parts lists etc.

The main body of the book starts with a history of rotary engines and their pros and cons. We then get to the meat: a 24 page history of the development of the ARI and BRl. This is excellent, and provides as good a history of the development of these engines as you're going to find; followed by a similar 27 page chapter on the BR2. There are still some gaps, but so long after the events it's possible that the complete story never will emerge.

Additional material includes a brief history of each aircraft type using Bentley engines, the same for sub-contractors, plus an illustrated schedule of all known surviving Bentley engines and 'Sopwith Survivors: We also see a good many fascinating original documents and drawings, and the book is provided with comprehensive references.