Volunteers with the outer rails of the phonograph, but in money, and the diminution or transformation of current on, 129. Mainspring, invention of, 412. Malleus, 272. Marconi, 140, 146. Marine chronometers, 415; delicacy of, 425. Marine speed governor, 71. Marine turbine, advantages of, 84. Maudslay, Henry, 363. Maxim, Sir Hiram, 348. Micrometer free wheel, 441. Micro-photography, 265. Microscope, 254; compound, 261, _263_; in telescope, 257; simple, _254_. Mineral oil, 392. Mirror, parabolic, 261, _262_; plane, _267_. Morse, 132, 145; code, 128; inker, 142; sounder, 132. Motor car, the, 92; electric, 177. Mouth, 307. Mowing-machines, 450. Musical sounds, 277. Nerve, auditory, 272; optic, 246. Nodes on.