McCloud River, why it is born half grown, [73]
Maine, advance of the sea upon its coasts, [219]
Mammoth, art note on, from the "Cavemen's Diary," [22];
ancient members of the elephant family that wore underclothes, [24]
Manchester, Mass., how the Old Men of the Mountain built its falls, [34]
Marble, how a New York City dike helps tell how marble is made, [97];
what the fossils have to say, [100];
how it is quarried, [103];
the mysteries in marble walls, [235];
when marble flows, [238];
the cloud effects in marble, [239];
how marble tells of earthquakes and other exciting things, [239]
Mars (planet), [6]
Meanders, engineering work of wandering rivers, [81];
meanders and the making of natural bridges, [83]
Mediterranean Sea, its connection with the making of the Alps, [136]
Mercury (planet), [6]
Metamorphism (defined), [98]