Gallileo, His Pendulum Experiment, 267 Gravesande, Prof. S., Letter to Sir Isaac Newton, 236 Haywood, John, His Device, 58 Heat and Energy Convertible and Commensurable, 261 Helmholtz, Notice of, 258 Honecort, Willars de, Account of His Device, 22 Horse-Power, Defined and Explained, 264 Hydro-Pneumatic Devices (See Table of Contents), 5 Hydrostatical Paradox, 118 Hydrostatical Paradoxical Balance, Article on, 305 Hydraulic and Hydro-Pneumatic Devices (See Table of Contents), 5 Inclined Planes and Rolling Weights (See Table of Contents), 5 Inclined Planes and Weights Devices, Unpublished. Noted by the Author, 73 Inclined Planes, Series of, 69 Italian Device, An, 92 Introductory Essay, 11 Jacobus, Dr., His Magnetic Device, 173 Joule, Notice of, 258 Jurin's Device, 176 Kenrick, Dr. William, His Remarks Concerning the Inventions of the Marquis of Worcester and Councillor Orffyreus and Perpetual Motion in General, 228 Langley, Prof. Samuel P., His Attempts and Labors at Heavier Than Air Flight, 14 Lardner, Ignatius, Attempts to Show Impossibility of Crossing Ocean With Steam Power, 14 Leonardo da Vinci (See Vinci). Läserson, Louis Diodor, His "Improvements in Production of Motive Power", 127 Legge's Hydro-Pneumatic Power Device, 146 Linley, John, His Hydraulic Device, 87 Liquid Air, as a Means of Perpetual Motion, 195 Lord Rayleigh (See Rayleigh). Mackintosh, F. S., Experiment by, 166 Magnetic Devices (See Table of Contents), 5 Magnetic-Driven Wheel, 164 Magnetic Pendulum, 163 Magnetic Semi-Circle, 172 Mechanic, A Journeyman (See "A Journeyman Mechanic"). Mechanics' Magazine, Article Published in, 278, 353