Despite—or perhaps because of—the tremendous effort which has been concentrated during and since the War on the development of the multistage axial flow compressor there has hitherto been a dearth of unrestricted information on this vitally important aspect of propulsion engineering. Most gas turbine textbooks devote a more or less brief chapter to this subject, and one finds scattered information in all manner of publications, but it has needed the enterprise of Messrs Springer to bring out the first really detailed textbook by one of the leading German authorities.