Mersenne, reflecting telescope, [108]

Messier, catalogue of nebulæ,[ 22]

Meteoric hypothesis of solar sustentation, [310];
of planetary formation, [311]

Meteoritic hypothesis of cosmical constitution, [376] [402]

Meteors, origin, [327] [328];
relations to comets, [327] [332]-334 [340]
Leonids, [328]-334 [338]
Perseids, [329] [332] [333] [341]
Andromedes, [334]-338
stationary radiants, [341]

Meunier, canals of Mars, [280]

Meyer, divisions of Saturn's rings, [302];
comet of 1880 [351]
cometary refraction, [353]
comet Tewfik, [362]

Michell, double stars,[ 17];
torsion balance, [261]
star systems, [426]

Michelson, velocity of light, [241]

Milky Way, grindstone theory,[ 14];
clustering power,[ 20],[ 26]
structure,[ 20],[ 41],[ 45],[ 47], [423]-425
centre of gravity,[ 40],[ 41]
frequented by Wolf-Rayet, temporary, and helium stars, [380] [399] [425]
by gaseous nebulæ, [402]
drawings and photographs, [424] [425]