In countless instances Perpetual Motion seekers of different races and living in separate countries, and, indeed, on different continents, centuries apart, have sought the attainment of Perpetual Motion by practically the same devices, and inventor after inventor has brought forth alleged inventions depending upon precisely the same underlying mechanical principle.
The author has attempted to classify the various devices presented in this book according to the underlying mechanical principles upon which the inventor chiefly relied for the success of his invention. Even this classification is extremely difficult and not well distinguished. Many of them, indeed most of them, depend for their success upon more than one mechanical principle, and the classifications thereby inevitably intermingle and overlap what otherwise would be their distinguishing boundaries. Still it is believed by the author that it is the best that could be adopted, and that no better or clearer classification is possible than the one here presented.
The various devices are classified by the author under the following heads:
Devices by Means of Wheels and Weights.
Devices by Means of Rolling Weights and Inclined Planes.
Hydraulic and Hydro-Mechanical Devices.
Pneumatic Siphon and Hydro-Pneumatic Devices.
Magnetic Devices.
Devices Utilizing Capillary Attraction and Physical Affinity.
Liquid Air as a Means of Perpetual Motion.