If you're seeking a digital copy of it's important to understand the nuances of copyright. The original 1937 edition is, depending on your jurisdiction, likely in the public domain, whereas the 1955 edition and subsequent reprints are not. This legal distinction shapes where you can find a legitimate copy:
The text explains why machines are physically constructed in specific ways (e.g., skewing rotor slots, fractional-pitch windings) by demonstrating the mathematical consequences of eliminating harmonics and optimizing flux distribution. Detailed Chapter and Subject Breakdown 1. The Physics of AC Circuits and Magnetism
How the physical shape of pole faces and winding arrangements affect the sinusoidal nature of generated EMF. Theory-alternating-current-machines-alexander-langsdorf-pdf
The polyphase induction motor is the workhorse of modern industry, and Langsdorf's treatment of it is highly praised.
: Many engineering departments keep physical copies in their reference sections. If you're seeking a digital copy of it's
Before examining the book, it is vital to understand the author. Alexander S. Langsdorf (1877–1973) was not merely a textbook writer; he was a giant of early electrical engineering education. A long-time professor at Washington University in St. Louis, Langsdorf possessed a unique ability to bridge the chasm between purely theoretical physics and the practical, gritty reality of rotating machinery.
Upon its release, Theory of Alternating-Current Machinery was met with critical acclaim. A review in Nature described it as a "large volume" that allowed the author to "adopt a comprehensive and at the same time broad and easily readable treatment," and stated it "can be thoroughly recommended". This high praise was well-deserved; for decades, it served as an essential reference for countless engineers and students. Detailed Chapter and Subject Breakdown 1
Many technical universities retain digital scans of foundational engineering texts within their internal networks for student and faculty research.
To find Langsdorf’s original text legally, consider: