thermometer in both cases to test the heat. The same fact with regard to
cold can be tried by holding both hands in a draught of cold air, the
one hand being wet, the other dry.

* * * * *

Lovers of natural history are not all aware what advantages the first
sharp frost offers them for the study of animal and vegetable life in
ponds. Thoreau, one of the most devoted admirers of nature, says in his
"Walden," that, "The first ice is especially interesting, being hard,
dark, and transparent, and affords the best opportunity that ever offers
for examining the bottom, where it is shallow; for you can lie at your
length on ice only an inch thick, like a skater insect on the surface of
the water, and study the bottom at your leisure, only two or three
inches distant, like a picture behind a glass."

* * * * *

[Illustration]

Country girls have an opportunity during the early darkness of winter
afternoons of appreciating one of the dangers which beset arctic
explorers during the long twilight which takes the place of day during
the winter months in those northern climes. In towns, the well-lighted
and well-paved streets make walking in the dusk as easy as in the day;
but girls, whose walks lead through fields and rough country lanes, know
how many trips and stumbles are caused by the uncertain light before
darkness sets in. Greely, in his terribly sad history of the sufferings
of his men during their arctic expedition, tells us how much their
difficulties were increased by this dimness of the light. It was