Mangles, [141]

Mantles for lamps, [88], [89], [90], [91], [95], [98]

Manufactured gas, [78], [89], [91]

Maximum thermometers, [234]

Mazda lamps, [82], [83], [84]

Measurements, [225]

Melting ice, [103]

Metal, conductivity of, [156], [158]

Meter, [229], [230], [231], [232]

Microbes, septic, [126]