Weeds, as soil makers, [9]

Winds, how they helped Mr. Lichen to discover the world, [1];
how they help the trees to march, [12];
their work in making, mixing, and transporting soil, [37]

Winter in the animal world, under the ground, [204]

Woodchuck (Groundhog), picturesque home of a Connecticut woodchuck, [134];
Mr. Woodchuck's winter quarters and his shadow, [219]

Wyoming, one of the homes of the prehistoric monsters, [27]

FOOTNOTES:

[ [1] "The Strange Adventures of a Pebble."

[2] "The Strange Adventures of a Pebble."

[3] All these things put together are called "weathering."

[ [4] Muir. "[The Mountains of California]."