Because snow, being a bad conductor, keeps in the internal heat of the dwelling, and prevents the cold outer air from taking away its warmth.
162. Why is snow, being composed of congealed water (and water being a better conductor than air), so good a non-conductor?
Because in the process of congealation it is frozen into crystalline forms, which, being collected into a mass, form a woolly body, thus proving the truthfulness of the Bible simile, which says, God "giveth snow like wool."
"He giveth snow like wool: he scattereth the hoar frost like ashes."—Psalm cxlvii.
FIG. 1.—CRYSTALS OF SNOW, AS SEEN THROUGH A MICROSCOPE.
163. Why does it frequently feel warmer after a frost has set in?